JPH06201968A - Centering device for lens - Google Patents

Abstract

PURPOSE:To prevent the distortion of a lens in the case of supporting the lens at the outside diameter part of the lens and to improve centering accuracy. CONSTITUTION:A lens supporting member (centering member) 1 is arranged so as to freely advance and retreat in the radial direction with respect to the optical axis center of the lens. A displacement sensor 3 detecting the relative position between the lens and the member 1 is arranged on the lens contact surface 1a of the member 1. A controller 4 controlling the advancing/retreating of the member 1 according to information from the sensor 3 is provided to control a motor 5 driving the advancing/retreating of the member 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens centering device, and more particularly to an outer diameter centering device that clamps the outer diameter of a lens to set the optical axis of the lens.

[0002]

2. Description of the Related Art Conventionally, as a method for mechanically centering an optical lens, there is a method called outer diameter centering. In this method, the optical axis of the optical lens is set by clamping the outer diameter of the optical lens at three to six points. Using this outer diameter centering to find the optical axis of the optical lens, then as a device for operating the above-mentioned optical lens,
For example, a device disclosed in Japanese Patent Laid-Open No. 3-146447 has been proposed.

FIGS. 7 and 8 (a) and 8 (b) show the centering device. FIG. 7 is a plan view, FIGS. 8 (a) and 8 (b) are partially vertical front views and main part front views. It is a figure. In the figure, reference numeral 51 denotes a scroll chuck that supports outer diameter support claws 53, 54, 55 fixed to a slide piece 52, and this scroll chuck 51 has insertion portions 58 of lenses 56 and 57 opened at its center, This insertion part 58
A disk-shaped main body 61 provided with a lens supporting unit 59 at the center of the disk, and provided with three guides 60 at equal intervals in the radial direction with respect to the insertion section 58;
A slide piece 52 mounted so as to be movable back and forth through a guide 60 in a length direction of 0, and rotatably attached to a bearing portion 62 of the main body 61 via a clip 63, and screwed to a screw 52a of each slide piece 52. And a timing belt 68 stretched between a pulley 65 fixed to the operation rotary body 64 and a pulley 67 fixed to a drive shaft 66a.
And a drive motor 66 connected to each other via.

In the centering operation of the centering device having such a structure, the rotation of the drive motor 66 is changed by the pulley 6.
7 is transmitted to the operating rotary body 64 of the slide piece 52 via the timing belt 68 and the pulley 65. When the operation rotating body 64 rotates, the slide piece 52 having the screw 52a that is screwed into the screw 64a of the operation rotating body 64 causes the outer diameter support claws 53, 54, 44 to move to the lenses 56, 5.
7, the lenses 56 and 57 are clamped, and the lens support unit 59 and the lenses 56 and 57 are aligned.

[0005]

Generally, when the outer diameter of a lens is mechanically clamped at 3 to 6 points in order to bring out the center of the lens, the clamping force can bring out the center of the lens. At the same time, however, the clamping force causes distortion of the lens. As described in JP-A-3-146447, outer diameter support claws 53, 5 arranged on the lenses 56, 57 in the radial direction with respect to the optical axis of the lenses 56, 57.
When clamped by pressing 4, 55, the lens 56, 57 is distorted by the clamping force, and when the clamp is released, the optical axis is displaced.
Outer diameter support claws 53, 5 due to the reaction force during clamping
Outer diameter support claws 5 due to moment load generated at 4, 55
3, 54, 55 cannot be positioned at precise positioning points, and as a result, the outer diameter support claws 53, 54,
Even during the centering work by pressing with the lens 55, the lenses 56 and 57 cannot be accurately positioned.

The present invention has been made in view of the above conventional problems, and does not cause distortion in the lens during outer diameter positioning for supporting the outer diameter of the lens, and further improves the centering accuracy. An object of the present invention is to provide a centering device for a lens that can be used.

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems, according to the present invention, a centering member for centering a lens can be moved forward and backward in a radial direction with respect to the center of the lens via a scroll chuck. In the centering device for the lens, the sensor for detecting the displacement between the centering member and the outer diameter of the lens is provided, and the relative position between the centering member and the lens is detected during the centering work. The centering member is provided with control means so that the centering member does not apply excessive pressure to the lens.

That is, according to the present invention, when the lens outer diameter is supported and the optical axis of the lens is taken out, the relative position between the lens supporting member and the lens is detected, and the lens supporting member is moved in the lens direction. The movement is controlled and the end of the centering work is determined.

FIG. 1 is a conceptual diagram of the present invention. The lens support member (centering member) 1 is arranged so as to be movable back and forth in the radial direction with respect to the optical axis of the lens 2. Further, a displacement sensor 3 that detects the relative position of the lens 2 and the lens support member 1 is arranged on the lens contact surface 1 a of the lens support member 1. A controller 4 for controlling the advance / retreat of the lens support member 1 based on the information from the displacement sensor 3 is provided to control a motor 5 for driving the advance / retreat of the lens support member 1.

In the lens centering device having the above structure, when the relative position between the lens 2 and the lens supporting member 1 is greatly separated during the lens centering operation, the lens supporting member 1 is fast-forwarded to the lens 2 Be moved towards. Thereafter, the lens 2 and the lens supporting member 1 are moved closer to each other, and the lens supporting member 1 is slowly moved toward the lens 2 with a small torque. At this time,
The lens 2 is only moved toward the center of the scroll chuck 6, and no excessive pressure is applied.

After that, when all the relative positions of the lens 2 and the three lens support members 1 become equal to or less than the contact distance between the lens 2 and the lens support member 1, the controller 4 causes the lens 2 to move.
Then, it is determined that all of the lens supporting member 1 are in contact with each other, and the centering work is completed. At this time, if the set value of the contact distance between the lens 2 and the lens supporting member 1 is set to be slightly larger than the value when the lens supporting member 1 actually clamps the lens 2, excessive pressure is applied to the lens 2. Without
The centering work can be completed.

[0012]

Embodiment 1 FIGS. 2 and 3A and 3B show a lens centering device according to Embodiment 1 of the present invention. FIG. 2 is a plan view, FIGS. b) is a partially longitudinal front view and a main part front view. In the figure, reference numeral 11 denotes a scroll chuck. The scroll chuck 11 includes a lens support unit 13 that supports a centered lens 12, and is perpendicular to the lens support unit 13 at equal intervals in the radial direction. 3 Article Guide 15
A disk-shaped main body 16 provided with a slide piece 17, a slide piece 17 arranged so as to be movable back and forth through the guide 15 in the longitudinal direction of the guide 15, and a clip 1 on a bearing portion 18 of the main body 16.
The slide piece 17 is rotatably attached via 9
20a screwed into the screws 17a formed on each bottom surface of the
A timing belt 24 stretched between an operating rotary body 20 formed on the upper surface and a pulley 23 fixed to the lower part of the operating rotary body 20 and fixed to a pulley 21 and a drive shaft 22a.
And a drive motor 22 for the operating rotary body 20 connected via the.

Further, outer diameter support claws 25, 26, 27 are fixed to each slide piece 17. Also, the lens contact surfaces 25a, 2 of the outer diameter support claws 25, 26, 27
6a and 27a include a lens 12 and outer diameter support claws 25 and 2
Displacement sensor 2 to detect the relative position with 6, 27
8, 29, and 30 are attached, and the displacement amounts detected by them are input to the controller 31. In the controller 31, displacement amounts input from displacement sensors 28, 29, 30 arranged on the outer diameter support claws 25, 26, 27, such as a laser displacement meter for measuring the positional relationship with the lens 12 in a non-contact manner. The drive motor 22 that drives the operating rotary body 20 is controlled by.

In the centering work by the lens centering device having the above-mentioned structure, the lens 12 is placed on the lens supporting unit 13 by the lens conveying means (not shown), the drive motor 22 is rotated, and the pulley 23 and the timing belt are rotated. Two
The operating rotary body 20 is rotated through the pulley 4 and the pulley 21. When the operation rotary body 20 rotates, the guide 15 is formed by the screw 20a formed on the upper surface of the operation rotary body 20 and the screw 17a of the slide piece 17 that is screwed into the screw 20a.
Along the axis of the lens 12 in the axial direction.

The rotation of the drive motor 22 at this time is controlled according to the flow shown in FIG. When the lens 12 is placed on the lens support unit 13 at the start of the centering work, the lens 12 and the outer diameter support tabs 25, 2 are
The distance between 6 and 27 is large. The drive motor 22 is rotated at a high speed and with a large torque until the lens 12 comes into contact with any of the outer diameter support claws 25, 26, 27. After that, the displacement sensors 28, 2
When any of the displacement amounts input from 9 and 30 becomes less than the specified value of the lens contact, the outer diameter support claws 25, 26,
It is determined that one of the lenses 27 has come into contact with the lens 12, and the drive motor 22 is rotated at a low speed and a low torque,
The lens 12 is moved to the center of the lens support unit 13 without applying a great force to the lens. After that, the displacement sensors 28, 2
When all the displacements input from 9, 30 are below the specified value for the centering end, the outer diameter support claws 25, 26, 2
Immediately before the lens 7 clamps the lens 12, the centering is completed, and the lens 12 is held from the lens supporting unit 13 by means of suction or the like. After that, the outer diameter support claws 25, 26, 27 are retracted as required to complete the centering operation.

According to this embodiment, the lens 1 for centering is provided.
In order not to apply a large pressure to the lens 2, the lens 12
Centering is performed without distortion. Further, since large pressure is not applied to the lens 12 by the outer diameter support claws 25, 26, 27, the outer diameter support claws 25, 2 due to the reaction force are not applied.
There is no misalignment due to deformation of 6, 27, etc., and highly accurate centering can be performed. Furthermore, the lens 12
Since the centering work is performed by detecting the relative positions of the outer diameter support claws 25, 26, and 27, stable centering can be performed without being affected by the variation in the outer diameter of the lens 12.

[0017]

Second Embodiment FIGS. 5 and 6 show a second embodiment of the present invention. FIG. 5 is a plan view and FIG. 6 is a partially longitudinal front view. In this embodiment, as shown in FIG. 5, the outer diameter support claws 25, 26, 27 are separated from the slide piece 17, and the outer diameter support claws 25, 26, 27 are the same as the slide piece 17 in the optical axis of the lens 12. It is attached to the linear guides 32, 33, 34 so as to be able to move back and forth in a direction perpendicular to and in the radial direction. The straight guides 32, 33, 34 are long objects having an H-shaped cross section, and the outer diameter supporting claws 25, 26,
It is fixed on the disc-shaped main body 16 so as to guide 27 and the lower groove straddles the slide piece 17. Then, the outer diameter support claws 25, 26, 27 and the slide piece 17
Are elastically connected by compression springs 35, 36 and 37.

The displacement sensor 30 is attached to one of the slide pieces 17, and the relative position between the slide piece 17 to which the displacement sensor 30 is attached and the outer diameter support claw 27 above the slide piece 17 can be detected. The configuration is different from the first embodiment described above. The other structure is the same as that of the first embodiment, and the description of the structure is omitted. In addition, the outer diameter support claws 25, 26, 27 are provided on the projecting upper portions of the outer periphery of each slide piece 17.
Guide plates 38, 39, 40 for slidingly guiding the upper surface of the guide plate are fixed by fixing pins 41, 42, 43, respectively. The guide plates 38, 39, 40 and the linear guides 32, 3 are fixed.
The outer peripheral surface of the slide piece 17 can be slidably contacted with the slide pieces 3, 34.

At the start of centering in the lens centering device having the above structure, the outer diameter support claws 25, 26, 27 are separated from the lens 12 and the outer diameter support claws 25, 26 are arranged. , 27 and slide piece 1
The distance 7 is kept at a constant distance by the compression springs 35, 36 and 37. From this state, the drive motor 22 is rotated at high speed and high torque, and the outer diameter support claws 25, 26,
27 is moved so as to approach the lens 12. The lens 12 and any one of the outer diameter support claws 25, 26, 27 come into contact with each other, and the lens 12 starts moving toward the center of the lens support unit 13. After that, when the lens 12 and all of the outer diameter support claws 25, 26, 27 come into contact with each other, the compression springs 35, 36, 37 are first compressed, and the distance between the outer diameter support claw 27 and the slide piece 17 starts to decrease. This state is detected by the displacement sensor 30, the rotation speed of the drive motor 22 is reduced, and the outer diameter support claws 25, 26, 27 are further reduced with low torque.
The drive motor 22 is rotated to bring the lens closer to the lens 12. After that, when the distance between the outer diameter support claw 25 and the slide piece 17 becomes equal to or less than the specified value for the centering end, the centering is finished immediately before the outer diameter support claws 25, 26 and 27 clamp the lens 12, The lens 12 is held by means of suction or the like from the support unit 13. After that, the outer diameter support claws 25, 26, 27 are retracted as required to complete the centering operation.

According to this embodiment, the compression springs 35 and 3 are provided for the lens 12 which is centered in the centering work.
Since only the compressive force provided by the lenses 6 and 37 is generated and the unnecessary compressive force is not applied to the lens 12, a large distortion is not generated in the lens 12, but the lens 12 is not distorted. It is possible to apply some restrictions. Further, since no more force than necessary is applied to the lens 12, the reaction force does not cause misalignment due to deformation of the outer diameter support claws 25, 26, 27. The force applied to the lens 12 can be easily adjusted by changing the spring constants of the compression springs 35, 36, 37. Furthermore, since the displacement sensor 30 can be one, control can be simplified.

[0021]

As described above, according to the lens centering device of the present invention, the centering step is performed by directly or indirectly detecting the lens and the centering member that comes into contact with the lens in the centering operation of the lens. By controlling, more accurate centering can be performed without being affected by the variation in the outer diameter of the lens and without causing internal distortion in the lens.

[Brief description of drawings]

FIG. 1 is a plan view showing the concept of the present invention.

FIG. 2 is a plan view showing a lens centering device of Embodiment 1 of the present invention.

FIG. 3 is a partially longitudinal front view (a) and a main part front view (b) showing the lens centering device of the first embodiment.

FIG. 4 is a flowchart showing the centering work of the first embodiment.

FIG. 5 is a plan view showing a lens centering device according to Embodiment 2 of the present invention.

FIG. 6 is a partially longitudinal front view showing a centering device for a lens according to the second embodiment.

FIG. 7 is a plan view showing a conventional centering device.

FIG. 8 is a partially longitudinal front view (a) and a main part front view (b) showing a conventional lens centering device.

[Explanation of symbols]

 1 Lens Support Member 2,12 Lens 3,28,29,30 Displacement Sensor 4,31 Controller 6,11 Scroll Chuck 16 Main Body 17 Slide Coat 25,26,27 Outer Diameter Support Claw

Claims (1)

[Claims] 1. A centering device for a lens comprising a centering member for centering a lens, which is arranged so as to be able to advance and retreat in the radial direction with respect to the center of the lens via a scroll chuck. A sensor that detects the displacement from the outer diameter of the lens is provided, and the relative position between the centering member and the lens is detected during the centering work so that the centering member does not apply excessive pressure to the lens. A lens centering device, characterized in that it has a control means for controlling.