JPH06320376A - Method and device for centering lens - Google Patents

Abstract

PURPOSE:To perform automatic regulation without being influenced by unevenness in the outside diameter of a lens to be centered when regulation is needed, and to provide a stable lens holding force, and stabilize lens quality, such as surface accuracy and eccentricity precision. CONSTITUTION:A V-block 1, an air cylinder 3, and a laser type displacement sensor 7 to detect the stop position of the cylinder head 3a of the air cylinder 3 are placed on a plate 2. The plate 2 is placed on a plate 8 through a slide table in a manner to be movable in X and Y directions. A stepping motor 10 and a computing control device 16 are placed on the plate 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens centering method and apparatus, and more particularly to a lens centering method and apparatus for clamping the outer peripheral portion of a lens to perform centering.

[0002]

2. Description of the Related Art Conventionally, various methods have been known as a method for mechanically centering a lens, one of which is called outer diameter centering. In this method, the outer peripheral portion of the lens is clamped at three to six points in order to bond a plurality of lenses or to process the lens such as a composite optical element in which a resin layer is formed on a spherical lens base material. The optical axis of the lens is taken out, and as a centering device used in the method,
For example, it is disclosed in the second embodiment of Japanese Patent Laid-Open No. 3-184813.

FIG. 8 shows the centering device. Figure 8
In the above, the lens 72 is supplied to the V groove 71a of the fixed V block 71, and the block 73 provided so as to be movable in the front-rear direction toward the V groove 71a is abutted so that the lens 72 can be centered.

Further, Japanese Patent Laid-Open No. 146447/1993 discloses that the outer peripheral portion of the lens is clamped and the optical axis is projected. The centering device includes a scroll chuck provided with an advancing / retreating mechanism in the radial direction with respect to the optical axis of the lens to be centered, and the outer peripheral portion of the lens moved in the radial direction is clamped by the advancing / retreating mechanism to perform the centering. It is configured to dispense.

[0005]

However, in the centering device described in the above-mentioned Japanese Patent Laid-Open No. 3-184813,
There has been a problem that the center of the clamped outer diameter is always varied due to the variation in the outer diameter of the supplied lens.

Further, in the centering device disclosed in the above-mentioned Japanese Patent Laid-Open No. 3-146447, there are two sliding parts among the three parts constituting the scroll chuck, the chuck body, the rotating body and the clip. Since it can occur in several places, the sliding area is large, and the sliding resistance greatly varies depending on which part slides. Therefore, there is a problem that the holding force when the lens is clamped varies, the eccentricity is not properly clamped, and the eccentricity is deteriorated, or stress is applied to the lens more than allowable and the surface accuracy is deteriorated.

Further, in each of the above-mentioned centering devices of the prior art, there is a problem that it is necessary to perform adjustment in advance so that the clamp center is aligned with the optical axis.

Therefore, the present invention was developed in view of the problems in the above-mentioned respective prior arts, and it is possible to accurately center the lens with the V block and hold the lens with a stable holding force. Further, it is an object of the present invention to provide a lens centering method and apparatus which can have an adjusting mechanism for at least one of the two adjustments in the XY directions.

[0009]

SUMMARY OF THE INVENTION The present invention provides a lens core for supplying and clamping a lens between an advancing / retreating mechanism movable in one direction perpendicular to the optical axis of the lens and a lens positioning member. In the centering method, a difference from a lens whose outer diameter is confirmed in advance is detected, and after the difference is converted into a difference of the outer diameter center, the centering lens is moved to correct the difference of the outer diameter center. This is a centering method.

Further, an advance / retreat mechanism capable of moving in one direction perpendicular to the optical axis of the lens, a lens positioning member, a sensor for detecting a difference between a centering lens and a lens whose outer diameter is previously confirmed. And a controller for processing a signal from the sensor to output a signal for operating the centering member, and a mechanism for moving the clamp center in at least one direction each time centering is performed.

The lens centering device configured as described above detects a difference in outer diameter of the supplied lens with respect to the master lens, converts the difference into a deviation of the outer diameter core, and calculates the value. By moving the centering member in the canceling direction, it is possible to cancel the variation in the center of the outer diameter of the supplied lens.

Even when it is necessary to adjust the clamp center of the centering device, if the adjustment amount is added to the movement amount for canceling the difference in outer diameter, the operation is performed only by changing the parameters of the control program. It will be possible. Further, the sliding area of the advancing / retreating mechanism for clamping the outer peripheral portion of the lens is extremely small, and the sliding resistance thereof is also very small, so that the lens holding force is always stably centered.

[0013]

Embodiment 1 FIGS. 1 to 4 show an apparatus used in this embodiment, FIG. 1 is a plan view, FIG. 2 is a sectional view taken along the line AA ′ of FIG. 1, FIG. 3 is a flow chart, and FIG. Is. 1 is 60 °
The V block 1 is fixed on the plate 2 (movable along the guide 6 when adjustment is necessary). Further, an air cylinder 3 having a cylinder head 3a is provided on the plate 2 so as to face the V block 1.
A lens support unit 5 supporting the centered lens 4 is arranged between the V block 1 and the cylinder 3.

A laser displacement sensor 7 for detecting the stop position of the cylinder head 3a of the cylinder 3 is mounted on the plate 2. Further, the plate 2 is mounted on the plate 8 via a slide table 9 so that the movement of the plate 2 in the Y direction is restricted and the plate 2 is movable in the X direction.
1 is transmitted to the pulley 12 via the timing belt 13, and the nut 14 is transmitted to the ball screw 15 fixed on the plate 2 so as to be movable in the X direction.

Next, the operation of the lens centering device of this embodiment will be described. First, after a master lens (not shown) is supported on the lens supporting unit 5, the air cylinder 3 is driven to move the cylinder head 3a in the V block 1 direction (X direction) and clamp it between the V block 1 and the cylinder head 3a. .
At that time, the stop position of the cylinder head 3a is measured by the laser displacement sensor 7 and set as the origin. After that, the cylinder head 3a is moved in the direction of the air cylinder 3 to release the clamp, and the master lens is taken out from the lens supporting unit 5.

Then, the centering lens 4 is supported by the lens supporting unit 5, and the air cylinder 3 is driven to move the cylinder head 3a in the V block 1 direction (X direction) as in the case of the master lens. Clamp between it and V-block 1. At that time, the stop position of the cylinder head 3a is measured by the laser displacement sensor 7. The lens 4 to be centered does not have all the same dimensions including the outer diameter. Tolerances are always set, and there are variations in them.

Therefore, a difference in outer diameter from the master lens occurs, and the stop position of the cylinder head 3a is not constant when the centering lens 4 is clamped. Then, the difference from the origin obtained in the previous step is detected. When the centered lens 4 is larger than the master lens, the center of the outer diameter is displaced toward the air cylinder 3. On the contrary, when it is small, it shifts to the V block 1 side.

The difference between the stop positions of the cylinder head 3a detected by the laser displacement sensor 7 is sent to the arithmetic and control unit 16. The arithmetic and control unit 16 includes an amplifier 17, a signal converter 18,
The control unit 19 and the stepping motor controller 20 are included in the amplifier 1 to detect the detected difference.
Amplified by 7, converted from analog output into a digital signal by the signal converter 18, and sent to the control device 19.
The controller 19 calculates the deviation of the outer diameter center from the detected difference.

The calculation formula for calculating the deviation AC of the outer diameter center from the difference DE from the origin obtained by the laser displacement sensor 7 is DF when the radius of the master lens is AG.
= DE sin α, GI = DF, GK = GI · tan
(90-α) / 2), JK = GK / cosα, AC = J
K (see FIG. 7). Further, the value is pulse-converted and output to the stepping motor controller 20, and the stepping motor 10 is operated at a desired rotational speed to rotate the ball screw 15 and move the plate 2 in the direction of canceling the difference between the outer diameter centers.

By this movement, the centers of the lenses 4 are aligned and the optical axis of the centering lens 4 coincides with the optical axis of the master lens.
After aligning the optical axes, the centered lens 4 and the lens supported by a device (not shown) are joined. Alternatively, a resin layer is formed on the centered lens 4 by an apparatus (not shown) to obtain a composite optical element or the like.

By evaluating the processed product obtained by the centering device according to the present embodiment, if adjustment in the Y direction becomes necessary, the V block 1 is moved along the guide 6 by an appropriate amount. (Transportation means not shown). If the average value of the eccentricity of the processed product deviates in the X direction for some reason, the above-mentioned control device 1
It is possible to obtain the same result as when the adjustment is performed, only by adding or subtracting that amount to the number of pulses determined by 9.

According to this embodiment, since the center of the outer diameter of the centered lens can be always located at the same position, the centering can be performed with high accuracy. Further, since it is possible to provide an adjustment function in the X direction, it is possible to deal with the need for adjustment only by changing the parameters of the control program.

In this embodiment, the air cylinder 3 is provided with the cylinder head 3a. However, the present invention is not limited to this, and the V block 1 and the cylinder head 3a are exchanged to replace the V block 1 with the air cylinder. 3 may be connected.

[0024]

[Embodiment 2] FIGS. 5 and 6 show an apparatus used in this embodiment, FIG. 5 is a plan view with a part omitted, and FIG.
It is a B'line sectional view. In this embodiment, the nut 15a of the ball screw 15 fixed to the plate 2 in the first embodiment is used.
Is fixed to the V block 1 and the deviation of the center of the outer diameter of the centered lens 4 is not canceled by moving the plate 2 but is canceled by moving the V block 1. Adjustment is also V block 1
Is performed by moving the plate 2 instead of moving the plate 2. Therefore, the slide table 9 mounted so that the plate 2 is movable only in the X direction is mounted so as to be movable only in the Y direction. Things that are different,
The other components have the same configuration, and the same components are designated by the same reference numerals and the description of the components is omitted.

In this embodiment, the same operation is performed until the stop position of the cylinder head 3a of the first embodiment is detected and the movement amount of the center of the outer diameter of the lens 4 for centering is calculated, but the position of the center of the outer diameter is corrected. Ball screw 1 via a pulley to
The V block 1 is moved by driving 5. When detecting the difference, it is necessary that the position of the V block 1 in the Y direction is at the position where the master lens is clamped.

When the outer diameter of the centering lens 4 is larger than that of the master lens, the center of the outer diameter of the centering lens 4 is located on the air cylinder 3 side. This means that the stepping motor is driven to move the V block 1 to the side opposite to the side where the air cylinder 3 is located, and the cylinder head 3
The center shift calculated from the stop position of a is moved.
Even if the V block 1 moves in this direction, the cylinder head 3a must be placed on the plate 2 so that a stroke allowance for continuing to keep the centering lens 4 on the V block 1 remains.

Conversely, when the outer diameter of the centering lens 4 is smaller than that of the master lens, the center of the outer diameter of the centering lens 4 is located on the V block 1 side. This means driving the stepping motor to drive the V block 1
Is moved to the side where the air cylinder 3 is located by the amount of the center deviation calculated from the stop position of the cylinder head 3a.

According to this embodiment, since the center of the outer diameter of the centered lens can be always located at the same position, the centering can be performed with high accuracy. Further, since it is possible to provide an adjusting function in the X direction, it is possible to deal with the need for adjustment only by changing the parameters of the control program.

[0029]

[Embodiment 3] FIG. 7 is a plan view in which a part of the apparatus used in this embodiment is omitted. In this embodiment, the correction of the center of the outer diameter of the lens 4 centered in the same manner as in the second embodiment is performed by the V block 1.
It is carried out by moving a and 1b, but a ball screw with a nut fixed is coupled along a guide 6 arranged so that the V blocks 1a and 1b divided in the Y direction can be moved in the Y direction. Two motors 10a, 10b through
It is configured to move by. Further, it has the same structure as that of each of the above-described embodiments except that there is no slide table for moving the plate 2 as in each of the above-mentioned embodiments, and the same components are denoted by the same reference numerals. And its description is omitted.

In this embodiment, the same operation is performed until the stop position of the cylinder head 3a of the first embodiment is detected and the movement amount of the center of the outer diameter of the lens 4 for centering is calculated. When the center diameter of the lens 4 is larger than that of the master lens, the center of the outer diameter is in the direction of the air cylinder 3, so the stepping motors 10a and 10b are controlled so that the distance between the V blocks 1a and 1b is increased. Conversely, when the centering lens 4 is smaller than the master lens, the V block 1
Stepping motor 10 so that the distance between a and 1b is narrowed.
a and 10b are controlled.

Then, when the difference in the outer diameter of the lens to be centered next is detected, the V block 1 is used as in the second embodiment.
It is necessary that the positions of a and 1b are at the positions where the master lens is clamped. However, if the relative positions of the V blocks 1a and 1b are always known with respect to the position and the amount by which the adjustment amount is adjusted can be moved, the V blocks 1a and 1b act as the master lens. There is no need to return to the clamped position.

In each of the above-described embodiments, only the adjustment in the X direction is performed by adding the adjustment amount to the correction amount of the center of the outer diameter and moving the V block by that amount, but in the present embodiment, it is performed in the Y direction. The feature is that the adjustment of is also performed automatically. The effect is that after the correction and adjustment in the X direction are completed, it is necessary to adjust the Y direction by a desired adjustment amount in the Y direction (evaluate the processed product obtained by the centering device according to the present embodiment. V block 1
This is to move a and 1b. At this time, the two motors rotate in the same direction when moving in the X direction, but rotate in different directions when used for moving in the Y direction.

According to this embodiment, the center of the outer diameter of the lens to be centered can be always located at the same position, so that the centering can be performed with high accuracy. Further, since it is possible to provide an adjusting function in the X and Y directions, it is possible to deal with the need for adjustment only by changing the parameters of the control program.

In each of the above-mentioned embodiments, the moving means for correction and correction to be automatically performed is not limited to the ball screw driving, and is not particularly limited as long as the displacement amount can be controlled. Similarly, the displacement sensor is not limited to the laser displacement sensor as long as it can measure in the order of μm and has an output function for the control device.

[0035]

As described above, according to the lens centering method and apparatus of the present invention, in the outer diameter centering of the lens, there is no influence of the variation in the outer diameter of the centered lens, and further adjustment is possible. It is possible to obtain a lens centering device that can be automatically performed when necessary. Further, since the area of the sliding portion is extremely small, a stable lens holding force can be obtained and the lens quality such as surface accuracy and eccentricity accuracy can be stabilized.

[Brief description of drawings]

FIG. 1 is a plan view showing a first embodiment.

FIG. 2 is a sectional view taken along the line A-A ′ in FIG.

FIG. 3 is a flowchart illustrating a first embodiment.

FIG. 4 is an explanatory view showing the first embodiment.

FIG. 5 is a plan view showing a second embodiment with a part omitted.

6 is a cross-sectional view taken along the line B-B ′ of FIG.

FIG. 7 is a plan view showing a third embodiment with a part omitted.

FIG. 8 is a schematic explanatory view showing a conventional example.

[Explanation of symbols]

 1 V Block 2, 8 Plate 3 Air Cylinder 3a Cylinder Head 4 Lens 5 Lens Support Yatto 6 Guide 7 Laser Displacement Sensor 9 Slide Table 10 Stepping Motor 16 Arithmetic Control Device

Claims (2)

[Claims] 1. A lens centering method for supplying and clamping a lens between an advancing / retreating mechanism movable in one direction perpendicular to the optical axis of the lens and a lens positioning member,
A feature of detecting a difference from a lens whose outer diameter is confirmed in advance, converting the difference to a difference of the outer diameter center, and moving the centering lens to correct the difference of the outer diameter center. How to center the lens. 2. A sensor for detecting a difference between an advancing / retreating mechanism movable in one direction perpendicular to the optical axis of the lens, a lens positioning member, a centering lens, and a lens whose outer diameter has been confirmed in advance. And a controller for processing a signal from the sensor to output a signal for operating the centering member, and a mechanism for moving the clamp center in at least one direction each time centering is performed. Centering device.