JPH0622798B2 - Lens polishing machine - Google Patents

Description

The present invention relates to a lens polishing apparatus.

[Background of the Invention]

Conventionally, polishing mainly for a lens has been conventionally performed as is known, and its basic principle has not changed. This principle will be described by taking a concave surface as an example, based on a conventional example of a lens polishing apparatus shown in FIG.

As shown in the figure, 1 is a lens which is an object to be polished,
Reference numeral 2 denotes a polishing tool, for example, a polishing dish 2 having a convex surface having a radius of curvature of the lens 1, which is forcibly rotated by a drive source, for example, a motor. The lens 1 is a lens holder, for example, a lens attachment plate 3
And a seat 5 for supporting a hairpin 4 which is commonly called a hairpin is provided on the opposite side of the lens sticking plate 3. A polishing load is applied to the hairpin 4 and, at the same time, a swinging motion having a constant amplitude is given by a motor. In the lens polishing apparatus configured as described above, the lens 1 is subordinately rotated by the rotational movement of the polishing dish 2 and the swinging movement of the pinion 4, and spherical polishing can be performed by supplying an abrasive.

By the way, when a minute spherical surface having a radius of curvature of 1 mm or less is polished by this lens polishing apparatus, there is a problem that the swinging of the polishing dish 2 causes the lens 1 to move, which makes the polishing unstable and breaks the edge. Also, when targeting a microsphere,
The swing amplitude of the hairpin 4 cannot be made large because the lens 1 is polished without being removed from the polishing dish 2. For this reason, it is difficult to obtain dependent rotation of the lens 1, and there is a problem that polishing does not proceed. Further, there is also a problem that the polishing load applied to the lens 1 cannot be suppressed to a small amount due to the mechanism. As described above, the conventional apparatus cannot polish the lens 1 with high precision.

Regarding this, optical element processing technology '81, Sho
Issued 56-10-10. Edit. Issued by: Japan Institute of Optical Technology twenty two
There are 0 to 222 (Keisuke Shiotani).

[Object of the Invention]

The present invention has been made in view of the above points, and an object of the present invention is to provide a lens polishing apparatus capable of polishing a lens with high accuracy.

[Outline of Invention]

That is, the present invention includes a lens, a lens holding base that holds the lens, a polishing tool that polishes the lens, and a drive source that drives the polishing tool, and the polishing tool is rotated to polish the lens. In the lens polishing apparatus configured to do so, the drive source is configured by a tool shaft having a polishing tool at the tip and a wind turbine device, and a guide hole having a clearance in a holding portion of the tool shaft of a guide that holds the tool shaft. Is provided so that the drive source can be swung with respect to the lens, thereby controlling the contact state between the lens and the polishing tool. Made possible to polish with high precision.

Example of Invention

Hereinafter, the present invention will be described based on the illustrated embodiments. FIG. 1 shows an embodiment of the present invention. Since the same parts as those of the prior art are designated by the same reference numerals, the description thereof will be omitted. In this embodiment, the drive source for driving the polishing tool 2a is formed by the wind turbine device having the swingable tool shaft 6. By doing so, the drive source is formed by the wind turbine device having the swingable tool shaft 6, so that stable polishing can be performed and the lens 1 can be highly accurately polished. The lens polishing device can be obtained.

That is, the drive source is formed by the wind turbine device having the swingable tool shaft 6, but the wind turbine device is formed by the impeller 7 fixed to the tool shaft 6 and the air ejection device for rotating the impeller 7. The air ejecting device is formed by an air supply nozzle 8 facing the impeller 7 and an air pump 9 that supplies air to the air supply nozzle 8. Tool shaft 6 is guide 10
The guide hole 11 having a clearance provided on the above is guided and supported so as to be swingable. As a result, the tool shaft 6
The contact state (including non-contact) of the polishing tool 2a provided at the tip of the lens 1 with the lens 1 can be adjusted. In the figure, 3a is a lens holder. By doing so, the lens 1 can be polished as described below. The lens holder 3a is adjusted to position the lens 1, and the tip of the polishing tool 2a is pressed against the surface to be polished of the lens 1. In this case, the polishing agent may be applied to the polishing tool 2a or the lens 1 or supplied from the outside, or a frame may be provided around the lens 1 to pool the polishing agent. In this state, the air pump 9 is operated to eject air from the air supply nozzle 8 toward the impeller 7. As a result, the polishing tool 2a is rotationally driven, and polishing proceeds. In this case, since the guide hole 11 has a clearance with respect to the tool shaft 6 as described above, the polishing tool 2a is guided and supported by the surface to be polished of the lens 1 even if the tool shaft 6 has rotational runout. The tool shaft 6 is not restricted in position and a stable polished state can be obtained. As described above, according to the present embodiment, the tool shaft 6 can be driven by the air flow without being mechanically connected, and stable polishing can be performed without being controlled by mechanical precision as in the conventional case. Thus, a high-quality polished surface with excellent surface roughness can be obtained without crushing the edges. Further, since the tool shaft 6 provided with the polishing tool 2a is rotated by the air flow to polish the surface to be polished of the lens 1 as a guide support surface, the polishing load applied to the lens 1 is reduced. be able to.

FIG. 2 shows another embodiment of the present invention. In this embodiment, an air ejection device is provided with an air supply nozzle 8 facing the impeller 7, an air pump 9 for supplying air to the air supply nozzle 8, and a flow valve provided in a part of the nozzle 8 for adjusting the ejection amount. 12, a non-contact displacement sensor 13 that controls the flow valve 12, and a displacement detection control device 14. By doing so, the air ejection device is provided in the air supply nozzle 8 facing the impeller 7, the air pump 9 that supplies air to the air supply nozzle 8, a part of the nozzle 8, and a flow valve that adjusts the ejection amount. 12, the non-contact displacement sensor 13 for controlling the flow valve 12, the displacement detection control device 14, etc. are formed so that the flow rate of air blown onto the impeller 7 can be adjusted, and the lens 1 is a polishing tool. 2a can be polished in a floating state.

That is, when the air pump 9 is operated and the air flow rate is increased above a certain amount, a levitation force is generated, and the polishing tool 2a floats while rotating. The flying height is detected by the non-contact displacement sensor 13 and input to the displacement detection control device 14. Based on this input signal, the displacement detection controller 14 controls the flow valve 12 to adjust the flying height. In this case, the polishing agent is pooled by providing a frame around the lens 1. By doing so, the polishing tool 2a is kept at a constant distance from the surface to be polished,
The lens 1 can be polished by the flow motion of the polishing agent accompanying the rotational motion of the polishing tool 2a. As described above, according to the present embodiment, the lens 1 is polished in a non-contact state with the polishing tool 2a, and a high-quality polished surface with a small processing strain can be obtained.

FIG. 3 shows still another embodiment of the present invention. In this embodiment, the lens 1a is flat. Also in this case, the lens 1a can be polished while the polishing tool 2b is levitated, and the same effect as the above case can be obtained.

That is, the polishing tool 2b also has a flat end. The guide hole 11a provided in the guide 10a has a longer guide surface than that in the case described above. When the air pump 9 is operated in this way, the lens 1a will be polished in the state of contacting or non-contacting the polishing tool 2a by adjusting the flow valve 12, but since the guide hole 11a is long, the tool is polished. The shaft 6 does not fall down at the time of starting the rotation, and the planar lens 1a can be stably polished.

FIG. 4 shows the polishing characteristics in each of the above examples. In the figure, the vertical axis represents surface roughness and the flying height, and the horizontal axis represents the rotation speed of the polishing tool, showing the relationship between the surface roughness and the flying height and the rotation speed of the polishing tool. As is clear from the figure, the flying height increases, that is, the surface roughness of the lens and the polishing tool decreases in the non-contact polishing area.

〔The invention's effect〕

As described above, according to the present invention, a lens can be polished with high precision, and a lens polishing apparatus capable of polishing the lens with high precision can be obtained.

[Brief description of drawings]

FIG. 1 is a partially longitudinal side view of an embodiment of the lens polishing apparatus of the present invention, FIG. 2 is a partially longitudinal side view of another embodiment of the lens polishing apparatus of the present invention, and FIG. FIG. 5 is a partial vertical sectional side view of still another embodiment of the lens polishing apparatus, FIG. 4 is a characteristic diagram showing the relationship between the surface roughness and the flying height of the lens polishing apparatus of the present invention, and the rotational speed of the polishing tool. FIG. 1 is a partially longitudinal side view of a conventional lens polishing apparatus 1, 1a ... Lens, 2a, 2b ... Polishing tool 3a ... Lens holder, 6 ... Tool shaft 7 ... Impeller, 8 ... Air supply Nozzle 9 …… Air pump, 10,10a …… Guide 11,11a …… Guide hole, 12 …… Flow valve 13 …… Non-contact displacement sensor 14 …… Displacement detection control device

Claims (3)

[Claims] 1. A lens, a lens holder for holding the lens, a polishing tool for polishing the lens, and a drive source for driving the polishing tool, and the lens is rotated by rotating the polishing tool. In a lens polishing apparatus configured to perform polishing, the drive source is configured by a tool shaft having a polishing tool at its tip and a wind turbine device, and a guide having a clearance in a holding portion of the tool shaft of a guide that holds the tool shaft. A lens polishing apparatus, wherein a hole is provided to allow the drive source to swing with respect to the lens, thereby adjusting a contact state between the lens and the polishing tool. 2. The lens polishing apparatus according to claim 1, wherein the wind turbine device is formed of an impeller fixed to the tool shaft and an air ejection device for rotating the impeller. 3. The air ejection device, an air supply nozzle facing the impeller, a part of the air supply nozzle, a flow valve for adjusting the ejection amount, and a non-contact for controlling the flow valve. The lens polishing apparatus according to claim 2, which is formed of a displacement sensor and a displacement detection device.