JPH07270662A - Centering device for lens and centering method - Google Patents

Abstract

PURPOSE:To provide a device and method capable of always centering a lens for the absolute center at a fixed position without being influenced by the variation in the outside diameter of lens and centering many kinds of lens having different diameters without a special set-up by determining a deviation of the absolute center of the lens to be centered based on the detected displacement and correcting the shifting portion. CONSTITUTION:After supporting a lens 5 with a supporting member 23, an operation rotating body 14 is rotated by a driving motor 16 through a pulley 15b and pulley 15a. At this time, the detecting amount from a displacement measuring instrument 30 is always sent to an arithmetic control device 31. When outside diameter supporting pawls 2, 3 and an outside diameter pressing pawl 4 are all brought into contact with the lens 5, the detection value of the displacement measuring instrument 30 becomes to vary, as the outside diameter pressing pawl 4 is constituted of a compliance mechanism by a guide 17 and a spring 19. At this time, the center position of the lens 5 is shifted in the back and forth direction of the outside diameter pressing pawl 4 by 1/2 shifting amount of the displacement measuring instrument 30. In order to correct the displacement amount of the shifting, a chuck base 22 is driven for the correction in controlling a piezoelectric element 27 by an operation control device 31.

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 position it.

[0002]

2. Description of the Related Art Generally, various methods are known as methods for mechanically centering a lens. One of the methods is called outline centering. In this method, the outer shape of the lens is clamped at 3 to 6 points to expose the optical axis of the lens, and various processing is performed on the lens. As an example of processing a lens by this centering of the outer shape, there is, for example, an apparatus disclosed in Japanese Patent Laid-Open No. 3-146447.

The structure of such an apparatus is composed of those shown in FIGS. 7 to 9, and its structure and operation will be described below with reference to the drawings. Reference numeral 101 is a scroll chuck that supports outer diameter support claws 102 and 103 and an outer diameter pressing claw 104. This scroll chuck 101 has an insertion portion 10 for the upper and lower cemented lenses 105 and 106 at the center.
7 are opened, and three guides 108 are arranged at equal intervals in the radial direction with respect to the axis of the insertion portion 107.
A disk-shaped main body 109, three slide pieces 110 mounted so as to be movable back and forth through the guide 108 in the longitudinal direction of the guide 108, and a clip 112 on a bearing portion 111 of the main body 109. The rotating body 113 for operation of each slide piece 110, which includes a screw 113a that is screwed into the screw 110a of each slide piece 110 that is rotatably mounted via the pulley 114a and the drive shaft 115a fixed to the rotating body 113, is fixed to the rotating body 113. Pulley 114 tied
and a drive motor 115 for the rotating body 113 connected via a timing belt 114c stretched between b.

The support claws 102 and 103 are fixed to the upper side of the slide pieces 110. Also,
The outer diameter pressing support claw 104 is attached to the slide piece 110 via a guide 117 so as to be movable back and forth, and is connected to a compression spring 118 as a pressing means fixed to a spring holder 116 fixed to the slide piece 110. Has been done. A hook 120 is fixed to the spring holding base 116 so as to constantly press the outer diameter pressing claw 104 in the acting direction by the pressing force of the compression spring 118. Further, a supporting member 119 is arranged in the center of the insertion portion 107 to support the lens 105.

In the centering of the lens having the above-described structure, after the supporting member 119 supports the cemented lenses 105 and 106, the driving motor 115 rotates the operating rotary body 113 via the pulley 114b and the pulley 114a. As a result, the outer diameter supporting claws 102, 1 are fixed by the screws 113a.
03 is guided by the guide 108 and moves a predetermined distance in the direction of the arrow in FIGS.
4 is guided by the guide 117 and moved by the compression spring 118 in the direction of the arrow in FIGS.
Center 6 while holding 6 at a constant pressure.

[0006]

However, in the lens centering method as in the above-mentioned prior art, the outer diameter support claws are always fed at a constant feed amount, and therefore, when the outer diameter of the lens varies, There was a problem that the absolute core of the lens that was taken out varied by the variation of the outer diameter. Also, if the outer diameter changes due to a change in the type of lens to be centered, the feed amount of the outer diameter support claws must be changed, and it takes time to change the setup, so centering of various types of lenses is required. When doing, there was a problem that the operating rate would be low.

The object of the present invention according to claims 1 and 2 is not influenced by the variation in the outer diameter of the lens, and the absolute center of the lens can always be centered at a fixed position, and various types of different-diameter lenses are not set up. There is that it can be centered with.

[0008]

The present invention has three advancing / retreating mechanisms which are movable in a direction perpendicular to the optical axis of the lens and in a direction toward the optical axis, and the advancing / retreating mechanisms are respectively arranged. In a device for centering the lens by contacting with the outer peripheral surface of the lens by moving the lens back and forth synchronously, a compliance mechanism provided in the forward / backward mechanism and having elasticity in the forward / backward direction and a displacement of the compliance mechanism are detected. A lens comprising: a sensor; a correction mechanism that corrects the center of the lens based on the amount of displacement so that the lens is always at a fixed position; and a control device that controls the correction mechanism and controls the advance / retreat mechanism. It is a centering device.

Further, by disposing three advancing / retreating mechanisms which are movable in a direction perpendicular to the optical axis of the lens and in a direction toward the optical axis, and advancing / retreating the advancing / retreating mechanisms in synchronization with each other, the lens In a method of centering a lens by bringing it into contact with an outer peripheral surface, a first step for confirming centering by detecting a displacement when the lens is centered by providing a compliance mechanism in the advancing / retreating mechanism; A second step of correcting the center of the lens so that it is always at a constant position based on the amount of displacement, and is a centering method for the lens.

The operation of the invention according to claims 1 and 2 is as follows.
One of the outer diameter support claws when the outer diameter of the centered lens is clamped by the outer diameter support claws that move in synchronization with the optical axis direction of the lens from three directions and the three outer diameter support claws clamp the lens. The driving of the outer diameter support claw is stopped at the moment when the detector detects the displacement of the compliance mechanism attached to the. Furthermore, by calculating the deviation of the absolute center of the lens that is centered from the detected displacement and correcting the deviation by the correction mechanism, the lens center is always adjusted regardless of the outer diameter of the lens. Can be set to a fixed position.

[0011]

Embodiment 1 FIGS. 1 to 4 show an apparatus used in this embodiment, FIG. 1 is a schematic configuration diagram, FIG. 2 is a plan view, and FIG. 3 is a partial side view showing an engaged state of a main body and a slide piece. 4 is shown in FIG.
It is an A section expanded sectional view of.

Reference numeral 1 denotes a scroll chuck which supports outer diameter support claws 2 and 3 and an outer diameter pressing claw 4. The scroll chuck 1 has an insertion portion 6 of a lens 5 opened at the center thereof and the insertion portion 6 has A disk-shaped main body 8 provided with three guides 7 arranged at equal intervals in the radial direction with respect to the axial center, and three slide pieces mounted so as to be movable back and forth through the guides 7 in the longitudinal direction of the guides 7. 9, 10, 11
And rotatably attached to the bearing portion 12 of the main body 8 via a clip 13,
Screw 1 that is screwed to screws 0, 11 9a, 10a, 11a
Via a timing belt 15c stretched between a rotary body 14 for operating each slide piece 9, 10, 11 provided with 4a and a pulley 15a fixed to the rotary body 14 and a pulley 15b fixed to a drive shaft 16a. Rotating body 14
Drive motor 16 of FIG.

The outer diameter support claws 2 and 3 are fixed to the upper sides of the slide pieces 9 and 10. Further, the outer diameter pressing support claw 4 is attached to the slide piece 11 so as to be movable back and forth through a guide 17 composed of a guide rail 17a and a guide table 17b, and the slide piece 1
It is connected to a compression spring 19 as a pressing means fixed to a spring holder 18 fixed to 1. Spring holder 18
A hook 20 is fixed to the outer diameter pressing claw 4 so as to constantly press the outer diameter pressing claw 4 in the acting direction by the pressing force of the compression spring 19. Further, a contact type displacement measuring head 21 is fixed to the spring holder 18 in order to measure the displacement of the outer diameter pressing claw 4 on the slide piece 11, and the displacement measuring head 2
Reference numeral 1 is connected to the displacement measuring device main body 30 by a cable.

The main body 8 of the chuck 1 is a chuck base 22.
The support member 23 is also fixed to the chuck base 22 so as to be positioned at the center of the insertion portion 6 so as to support the lens 5. The drive motor 16 described above is fixed to the lower surface of the chuck base 22. With the above-described configuration, the outer diameter support claws 2 and 3 and the outer diameter pressing claw 4 are moved forward and backward by driving the motor 16, so that the outer peripheral surface of the lens 5 is moved to 3 mm.
A lens centering mechanism for centering the lens 5 by supporting it from the direction is configured.

Reference numeral 24 denotes an apparatus base that supports the entire apparatus of this embodiment, and a guide rail 25 is fixed to the upper surface of the apparatus base 24 so that the outer diameter pressing claw 4 can be moved back and forth in the same direction. The chuck base 22 is mounted on the table 26 of the guide rail 25. A base 28 is provided upright on the device base 24, and the piezoelectric element 27 is fixed to the piezoelectric element base 28. A tension spring 29 is attached to the piezoelectric element base 28. This tension spring 2
Reference numeral 9 denotes the side surface 22 a of the chuck base 22 and the piezoelectric element 2.
In order to apply a preload to the contact surface 27a of the chuck 7, the side surface 22a of the chuck base 22 is attached.

With the above-described structure, the chuck base 22 is structured such that the piezoelectric element 27 guides the guide rail 25 and allows the outer diameter pressing claw 4 to move slightly in the advancing / retreating direction. The displacement measuring device 30 is the arithmetic and control unit 3
1 is connected to the arithmetic and control unit 31 by a cable in order to send the measured value, and the arithmetic and control unit 31 is connected by a cable to control the piezoelectric element 27 and the motor 16.

In the centering of the lens using the apparatus having the above structure, after the lens 5 is supported by the support member 23, the drive motor 16 drives the pulley 15b and the pulley 15a.
The operating rotator 14 is rotated via the. This allows
The outer diameter support claws 2 and 3 and the outer diameter pressing claw 4 are guided by the guide 14 by the screw 14a and moved in the arrow direction in FIG. During this time, the detected value from the displacement measuring device 30 is always sent to the arithmetic and control unit 31. When the outer diameter supporting claws 2 and 3 and the outer diameter pressing claw 4 all come into contact with the lens 5, the outer diameter pressing claw 4 constitutes the compliance mechanism by the guide 17 and the spring 19, so the detected value of the displacement measuring device 30. Begins to displace. The arithmetic control unit 31 detects this change in the detected value, and the arithmetic detection unit 31 stops driving the motor 16.

By the above operation, the lens 5 is gripped by the outer diameter support claws 2 and 3 and the outer diameter pressing claw 4 by a constant gripping pressure, that is, the elastic force of the spring 19. At this time, the lens 5
The position of the center of is shifted by ½ of the displacement amount of the displacement measuring device 31 in the advancing / retreating direction of the outer diameter pressing claw 4. In order to correct the shift amount for this shift, the arithmetic and control unit 31 controls the piezoelectric element 27 to drive the chuck base 22 and correct it.

According to this embodiment, since the outer diameter support claws 2 and 3 and the outer diameter pressing claw 4 are driven by the single drive motor 16, the control of the drive motor can be performed relatively easily. Further, since the piezoelectric element 27 is used to correct the deviation amount,
The deviation amount of the center of the lens 5 can be accurately corrected in units of sub μm, and the lens can be centered with high accuracy.

[0020]

Embodiment 2 FIGS. 5 and 6 show an apparatus used in this embodiment, FIG. 5 is a schematic configuration diagram, and FIG. 6 is a sectional view. The apparatus of the present invention comprises a centering mechanism section 51, a displacement measuring instrument 52, and an arithmetic and control unit 53. The centering mechanism section 51 is
A supporting member 56 is fixed to the center of the centering base 54 so as to support the lens 55. The supporting members 56 are arranged at equal intervals in the radial direction with respect to the optical axis of the lens 55, and the outer diameter supporting claws 57 and 58 of the lens 55 are formed. Mechanism 60, 6 for advancing and retracting the outer diameter pressing claw 59
1, 62 are arranged.

A forward / backward moving mechanism 60 for the outer diameter support claws 57, 58,
The configuration of 61 is such that the outer diameter support claws 5 are provided on the centering base 54.
Guide rail 63 as a guide for advancing / retreating 7,58
Is fixed, and an outer diameter support claw 5 is mounted on a guide table 64 slidably mounted on the guide rail 63.
7, 58 are attached respectively. Further, a nut 66 of a ball screw 65 is attached to the outer diameter support tabs 57 and 58 so as to drive them in the advancing and retracting directions. One end of the ball screw 65 is rotatably attached to a ball screw base 67 erected on the centering base 54, and the other end is attached to a motor 69 attached to a motor base 68 erected on the centering base 54. It is mounted to be rotated by.

In the construction of the advancing / retreating mechanism 62 of the outer diameter pressing claw 59, a guide rail 70 is fixed on the centering base 54 to guide the outer diameter supporting claw 59 in the forward / backward direction, and a guide table is mounted on the guide rail 70. 71 is slidably attached. On the guide table 71, a guide rail 72 is provided to guide the outer diameter pressing claw 59 in the advancing / retreating direction.
Is fixed, and an outer diameter pressing claw 59 is mounted on a guide table 73 slidably mounted on the guide rail 72. In addition, the guide table 71,
A cylinder 74 for pressing the outer diameter pressing claw 59 with a constant pressure is fixed, and the tip of a rod 75 of the cylinder 74 is attached to the outer diameter pressing claw 59.

A head 76 of the non-contact displacement measuring instrument 52 is fixed above the cylinder 74 to measure the displacement of the outer diameter pressing claw 59 on the guide table 71.
6 is connected to the non-contact displacement measuring device 52 by a cable. Further, a nut 78 of a ball screw 77 is attached to the side surface of the guide table 71 so as to drive it in the forward / backward direction. One end of the ball screw 77 is rotatably attached to a ball screw base 79 erected on the centering base 54, and the other end is attached to a motor base 80 erected on the centering base 54. It is mounted to be rotated by.

The arithmetic and control unit 53 is connected to the non-contact displacement measuring instrument 52 by a cable in order to take in the measured value of the non-contact displacement measuring instrument 52 described above. Further, the arithmetic and control unit 53
Are connected by cables to control the drive motor 69 of the outer diameter support claws 57 and 58 and the drive motor 81 of the outer diameter pressing claw 59.

In the centering of the lens using the apparatus having the above-described structure, the lens 55 is supported by the supporting member 56, and the drive motors 69 and 81 are driven in synchronization to drive the ball screws 65 and 77. Outer diameter support claws 5
7, 58 and the outer diameter pressing claw 59 are moved in the directions of the arrows in FIGS. 5 and 6. During this time, the detected value from the non-contact displacement measuring instrument 52 is always sent to the arithmetic and control unit 53. When the outer diameter support claws 57 and 58 and the outer diameter pressing claw 59 all come into contact with the lens 55, the outer diameter pressing claw 59 constitutes the compliance mechanism by the guide rail 72 and the cylinder 74, and therefore the non-contact displacement measuring device 52. The detected value of starts to change. The arithmetic and control unit 53 detects this change in the detected value, and the arithmetic and control unit 53 stops driving the motor 69 and the motor 81.

By the above operation, the lens 55 holds the outer diameter supporting claws 57, 57 with a constant gripping pressure, that is, the thrust of the cylinder 74.
58 and the outer diameter pressing claw 59. At this time, the center position of the lens 55 is 1/2 of that of the non-contact displacement measuring instrument 52.
The outer diameter pressing claw 59 is shifted in the advancing / retreating direction.
In order to correct the shift amount for this shift, the arithmetic and control unit 53
5 drives the motor 69 to drive the outer diameter support claws 57 and 58 in the direction opposite to the arrow in FIGS.
Drive in the direction of the middle arrow. The amount of movement of the outer diameter support claws 57, 58 and the outer diameter pressing claw 59 at the time of correction in this embodiment is
If the shift amount is L, then the outer diameter support tabs 57, 58
Is L × 1 / (2 × SIN 60 °), and the outer diameter pressing claw 59 is L × 1/2.

According to this embodiment, since the non-contact displacement measuring instrument 52 is used for the displacement of the outer diameter pressing claw 59, the head 76 of the non-contact displacement measuring instrument 52 is not affected and the displacement is highly accurate. The lens 55 can be gripped by the gripping force. Further, since the motor for driving the claw for supporting the outer diameter is also used for correcting the deviation amount, the centering mechanism can have a simple structure.

[0028]

The effects of the present invention according to claims 1 and 2 are that the moment the lens is gripped is detected by the displacement measuring device, and the driving of the outer diameter support claws is stopped. Instead, the lens can always be gripped with a constant gripping force, and centering can be performed steplessly even when a lens having a different diameter and a different diameter is centered. Further, since the centering clamp without distortion of the lens can be performed, the optical element can be processed with high accuracy.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram illustrating a first embodiment.

FIG. 2 is a plan view showing the first embodiment.

FIG. 3 is a partial side view showing the first embodiment.

FIG. 4 is an enlarged cross-sectional view of part A in FIG.

FIG. 5 is a schematic configuration diagram showing a second embodiment.

FIG. 6 is a cross-sectional view showing a second embodiment.

FIG. 7 is a cross-sectional view showing a conventional example.

FIG. 8 is a plan view showing a conventional example.

FIG. 9 is a partial side view showing a conventional example.

[Explanation of symbols]

 1 Scroll chuck 2,3 Outer diameter support claw 4 Outer diameter pressing claw 5 Lens 8 Main body 9,10,11 Sliding top 14 Rotating body 16 Drive motor 17 Guide 19 Compression spring 21 Displacement measuring head 22 Chuck base 23 Supporting member 24 Device Base 27 Piezoelectric element 29 Extension spring 30 Displacement measuring device 31 Arithmetic control device

Claims (2)

[Claims] 1. A lens reciprocating mechanism is provided at three points which are movable in a direction perpendicular to the optical axis of the lens and toward the optical axis, and the reciprocating mechanism is moved forward and backward in synchronization with each other. In a device for centering a lens by bringing it into contact with an outer peripheral surface, a compliance mechanism provided in the advancing / retreating mechanism and having elasticity in a forward / backward direction, a sensor for detecting displacement of the compliance mechanism, and a center of the lens based on the displacement amount. A lens centering device comprising: a correction mechanism that corrects so as to always be a constant position; and a control device that controls the correction mechanism and controls the advance / retreat mechanism. 2. An advance / retreat mechanism that is movable in a direction perpendicular to the optical axis of the lens and away from the optical axis is provided at three points, and the advance / retreat mechanism is advanced and retracted in synchronization with each other, whereby the lens In a method of centering a lens by bringing it into contact with an outer peripheral surface, a first step for confirming centering by detecting a displacement when the lens is centered by providing a compliance mechanism in the advancing / retreating mechanism; A second step of correcting the center of the lens so that it is always at a fixed position based on the amount of displacement.