JP3169249B2 - Lens centering device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for centering a lens.

[0002]

2. Description of the Related Art Conventionally, a lens with high optical surface accuracy generally has a slight eccentricity. A lens having no eccentricity can be obtained by centering the optical axis and shaving the lens periphery to a desired outer diameter. Do the precautionary work to be done. FIG. 13 shows a conventional optical centering and centering method. The lens 91 is temporarily bonded to the holder 92 with an adhesive 93 such as pine tar. next,
The holder 92 is rotated, the reflected image is visually measured by the autocollimator 94, and the lens 91 is moved to a position where the reflected image is free from deflection, and is fixed with the adhesive 93. Then, the lens 91 is finished to a desired outer diameter without eccentricity by grinding with a grindstone 95 such as diamond. FIG. 14 shows a method of mechanical centering and centering. When the lens 91 is clamped between the coaxially opposed bell holders 96, the optical axis of the lens 91 slides by the bell effect until it coincides with the axis between the bell holders 96. Then, the lens 91 is cut by a grindstone 95 such as diamond. Is finished to a desired outer diameter without eccentricity.

[0003]

However, in each of the above-mentioned conventional centering devices, the peripheral edge of the lens is shaved with a grindstone.
Approximately 60 for centering with a lens with an outer diameter of about 30mm
It takes a long time of seconds. And there was a fault that processing time became long, so that an outer diameter became large. Further, since the cutting is performed along the circumference of the lens, it is possible to center the lens only in a circular shape, and it is impossible to center the lens in an arbitrary shape.

Accordingly, the present invention has been developed in view of the drawbacks of the above-described prior arts, and provides a lens centering apparatus capable of centering a lens in an arbitrary shape with high accuracy in a short time. The purpose is to do.

[0005]

A lens centering device according to the present invention is a lens which forms a non-eccentric lens by centering an eccentric lens with respect to its optical axis and shaving the outer periphery. In the centering device, an ultrasonic processing unit for providing a tool formed in a cylindrical centering shape for centering the outer periphery of the lens at the tip and longitudinally vibrating the tool is provided, and the ultrasonic processing unit is provided in the ultrasonic processing unit. A lens support member for supporting the eccentric lens so that the outer periphery of the eccentric lens is punched by a cylindrical tool, a shaft of a cylindrical tool provided in the ultrasonic processing unit, and the lens A centering unit that matches the optical axis of the lens supported by the support member, and a unit that supplies loose abrasive grains to a processing portion of the cylindrical tool, and Shape the perimeter It is obtained as punching in the direction of the optical axis of the lens so as to. The centering unit includes a lens moving mechanism, a paraxial eccentricity measuring unit, and a control unit that processes a signal from the paraxial eccentricity measuring unit to control the movement of the lens moving mechanism. is there.
Further, the lens centering device of the present invention is a lens centering device which forms a non-eccentric lens by centering a decentered lens with respect to its optical axis and shaving the outer periphery. An ultrasonic machining unit that provides a tool formed in a cylindrical centering shape for centering the tip and vertically vibrates the tool, and the cylindrical tool provided in the ultrasonic machining unit has the eccentricity. A lens support member that supports the eccentric lens so that the outer periphery of the lens is punched, a shaft of a cylindrical tool provided in the ultrasonic processing unit, and light of the lens supported by the lens support member. A centering unit for matching the axis, a means for supplying loose abrasive grains to a processing portion of the cylindrical tool, and after punching an outer periphery of the lens in the optical axis direction of the lens with the cylindrical tool, Engineering And it is obtained so as to anda water tank for submerging the fitted lenses the tool.

FIG. 1 is an exemplary conceptual view of a lens centering device according to the present invention. Reference numeral 1 denotes the ultrasonic processing unit for dropping the outer periphery of the lens 3. Ultrasonic processing unit 1
Is provided with a cylindrical tool 11 formed in a desired centering shape at a portion in contact with the lens 3 as a workpiece. The lens 3 supplied to the centering device is positioned by the centering unit 4 with respect to the tool 11 of the ultrasonic processing unit 1 such that both axes are aligned. After that, the lens 3 and the tool 1 are brought into contact with each other so as to have a processing pressure, and the ultrasonic processing unit 1 longitudinally vibrates the cylindrical tool 11, so that the lens 3 has a centering shape at the tip of the tool 11. The outer circumference is dropped and centered.

[0007]

Embodiment 1 FIG. 2 is a partially sectional front view showing the present embodiment. Reference numeral 1 denotes an ultrasonic processing unit. In the ultrasonic processing unit 1, electric energy supplied from an oscillator 12 is converted into mechanical longitudinal vibration (ultrasonic vibration) by a magnetostrictive vibrator 13. The cone 14 expands and transmits the amplitude of this vibration, and furthermore, a horn 15 attached to the tip of the cone 14.
To resonate the amplitude to further expand and match. The tip of the cone 14 is provided with a tool 11 integrally connected.

[0008] The tool 11 has a cylindrical portion at the tip end, and the inside of the tool 11 has a desired lens 3 after the centering operation.
It matches the outer diameter. The tool 11, the cone 14, and the horn 15 are hollow so as to penetrate the shaft 41a of the bell upper shaft 41. Further, a suspension 19 using water and silicon carbide (SiC) as abrasive grains is supplied from a supply pipe 18 connected to an abrasive grain supply device (not shown) toward a processing portion at the tip of the tool 11. It is configured as follows. A vibrator cooling water is accommodated in a vibrator case 16 fixed by the flange 14a of the cone 14, and the vibrator cooling water is circulated. Reference numeral 17 shown on the side of the vibrator case 16 denotes an injection / drainage pipe.

Reference numeral 41 denotes a bell upper shaft, the tip of which is formed so as to fit inside the tool 11 in a state where the shaft center coincides with the tool 11. The shaft 41a has the cone 14 and the horn 15
And can be moved up and down by a mechanism (not shown) at the same time or separately from the ultrasonic processing unit 1, and is rotatable. Reference numeral 42 denotes a bell lower shaft, which also has a function as a lens support member because the lens 3 as a workpiece is mounted thereon, and acts so as to produce a bell effect in a state where the lens 3 is sandwiched between the bell upper shaft 41 and the lens 3. The base 4 is held in a state where the axis of the bell upper shaft 41 is aligned with the center of the bell so that the centering unit is formed.
3 and is rotatably fixed on it.

A motor 44 rotates the bell lower shaft 42 via a belt 45. A water tank 46 is placed on the base 43 in addition to the bell lower shaft 42. The base 43 is mounted on a movable movable table 47, and is configured so that the bell lower shaft 42 and the water tank 46 can be switched to a position directly below the ultrasonic processing unit 1 by a cylinder 48. Aquarium 46
Water 49 is stored inside.

In the apparatus having the above-described configuration, first, the lens 3 as a workpiece is mounted on the bell lower shaft 42. Next, the bell upper shaft 41 is lowered, and the lens 3 is sandwiched between the bell upper shaft 41 and the bell lower shaft 42 to center the lens 3 by the bell effect. Next, the ultrasonic processing unit 1 is lowered and the lens 3
And the tool 11 are brought into contact with each other.
A working pressure is applied between the two by a weight (not shown) placed above.

Next, the oscillator 12 is operated to supply high-frequency energy of 10 KHz to the vibrator 13, and the vibrator 13 converts this energy into mechanical vibration of the same frequency. By this conversion, the amplitude of the mechanical vibration of about 30 μm is obtained, and the amplitude is expanded through the cone 14 and the horn 15, and the vibration is matched to give the vibration to the tool 11. At the same time, the ultrasonic processing unit 1 is lowered while supplying the suspension 19 from the supply pipe 18, and the lens 3 sandwiched between the bell upper shaft 41 and the bell lower shaft 42 while maintaining an appropriate processing pressure. Centering (punching). Since the bell lower shaft 42 is smaller than the outer shape (outer circumference) of the tool 11,
The shape is such that the tool 11 does not interfere after punching the lens.

At the time of this processing, the lower shaft 42 of the bell is rotated by a motor 44 via a belt 45 so that the lens 3 is rotated.
Since the tool 11 also rotates relative to the tool 11, even if the tool 11 has uneven wear, centering is performed in a perfect circle. The cutting speed by the lowering of the ultrasonic processing unit 1 is about 1 mm / 10
The cutting is completed in about 30 seconds even with a lens having a thickness of 3 mm. After the processing, the ultrasonic processing unit 1 is raised to separate the tool 11 from the lens 3, and the oscillation is stopped.

At this time, the centered lens 3 is attached to the tool 1
There is a case that it cannot be detached while being fitted to 1. Then, the base 43 on the moving table 47 is moved by the cylinder 48 so that the water tank 46 containing water 49 comes under the ultrasonic processing unit 1. Thereafter, the ultrasonic processing unit 1 is set so that the tool 11 with the lens 3 fitted therein enters the water 49 (submerges).
Is lowered. Next, when ultrasonic waves are oscillated in a state of being submerged in the water 49 in the same manner as described above, the abrasive grains sandwiched between the lens 3 and the tool 11 are dropped and the fitting is loosened. It is dropped and the preparatory work ends. In the above embodiment, high-frequency vibration energy of 10 KHz was supplied to the oscillator, but it may be supplied in the range of about 10 to 30 KHz. When the frequency is high, the finish of the outer shape of the workpiece can be improved. it can.

According to the present embodiment, since the lens 3 is punched out of the internal shape of the tool 11 with the abrasive vibrated by the tip of the tool 11, the lens 3 having a circular center can be obtained in a short time. Can be.

As a modification of this embodiment, the lens 3
The outer periphery can be centered not only in a circle but also in any shape. In this case, the inside shape of the tip processing portion of the tool 11 is an arbitrary shape that matches the desired lens outer shape after the centering operation. The difference from this embodiment is that centering is performed without rotating the bell lower shaft 42. That is, the lens 3 is attached to the tool 1
Punching is performed without rotating relative to 1. With the above configuration and operation, the lens 3 can be centered in an arbitrary external shape in a short time.

[0017]

[Embodiment 2] FIG. 3 is a partially cutaway front view showing this embodiment. In this embodiment, only parts different from the first embodiment will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.

The bearing 20 is a flange 1 of the cone 14.
4a and the vibrator case 16, the tool 11,
The vibrator 31, the cone 14, and the horn 15 are rotatably supported. The vibrator 31 is a piezoelectric element type vibrator and converts electric energy from the oscillator 12 into longitudinal vibration. The slip ring 32 transmits electric energy from the oscillator 12 to the rotatable vibrator 31. The motor 21 rotates the tool 11, the vibrator 31, the cone 14, and the horn 15 of the ultrasonic processing unit 1 via the belt 22. The lens support member 50 has an annular lens receiving surface, is rotatably attached to the base 43, and is rotated by a lens motor 51 via a lens belt 52.

The paraxial eccentricity measuring section 53 is arranged above the ultrasonic processing unit 1 so that its optical axis coincides with the rotation axis of the lens supporting member 50. This paraxial eccentricity measuring unit 5
Reference numeral 3 has a function of projecting light to be condensed at the center of the paraxial curvature of the lens 3 and obtaining the amount of eccentricity from the reflected light.
The tool 11, the vibrator 31, the cone 14, and the horn 15 are hollow near the axis in order to allow the light from the paraxial eccentricity measuring unit 53 to pass therethrough.

A suction pad 33 is connected to a vacuum generator 35 via a pipe 34. A rotary joint (not shown) is arranged in the middle of the piping pipe 34, and the suction pad 33 is arranged so as to be rotatable with the lens support member 50. Vacuum generator 3
When a vacuum is generated in 5, the lens 3 on the lens supporting member 50 is fixed on the lens supporting member 50 in such a manner as to be attracted to the suction pad 33.

The arithmetic unit 54 functioning as a control unit determines that the optical axis of the lens 3 coincides with the axis of the tool 11 of the ultrasonic processing unit 1 based on the amount of eccentricity of the lens 3 measured by the paraxial eccentricity measuring unit 53. The movement instruction is given to the pin drive unit 55. The pin driving unit 55 is disposed at three or four equal positions around the lens 3, and
The user makes a movement to adjust the posture of the lens 3 on the zero.

FIG. 4 shows the configuration of the pin drive unit 55 in detail. The pin 56 is movably held in the axial direction by a stage 57, and is urged by a spring 58 in a direction in which the pin 56 retracts. The feed screw 59 is connected to the pin motor 63 via the pulleys 60 and 61 and the belt 62, and is configured so that the pin 56 can be slightly moved back and forth by the rotation of the pin motor 63. The stage 64 has a structure that supports the entire pin fine movement mechanism movably in the axial direction of the pin and is moved by an air cylinder or a motor (not shown).
The stopper 65 determines the accuracy of the stop position of the stage 64 on the lens side, and the stop position can be adjusted with high accuracy.

In the apparatus having the above configuration, first, the lens 3 which is a workpiece is placed on the lens supporting member 50. next,
The lens motor 51 rotates the lens support member 50 once via the lens belt 52. At this time, the paraxial eccentricity measuring unit 5
At 3, the eccentric amount and direction of the lens 3 with respect to the ultrasonic processing unit 1 are detected.

For the detected amount of eccentricity, the arithmetic unit 54 gives a command to move the lens 3 in a direction to eliminate the amount of eccentricity to the pin drive unit 55. The pin drive unit 55 receives the command, first the stage 64 advances, and stops just before the pin 56 touches the lens. Next, while observing the optical axis position of the lens 3 by the paraxial eccentricity measuring unit 53, the pins 56 are advanced one by one by the fine movement mechanism, and the lens 3 is slid over the lens support member 50 to form a spot image of the optical axis. Detects movement. The axial center of the lens support member 50 and the ultrasonic processing unit 1
Since the center axis of the tool 11 is aligned with each other, each pin 56 is slightly moved back and forth, and the lens on the lens support member 50 is slid so that the spot image of the optical axis is centered. The centering of the lens 3 with respect to the tool 11 is performed only by this.

In the centered state, the pin 56 is fixed at that position to hold the lens 3, and the vacuum generator 35 is further operated to draw the lens 3 toward the lens support member 50 via the suction pad, thereby causing the lens 3 to move. 3. Make sure that 3 is retained. Thereafter, the ultrasonic processing unit 1 is lowered,
The centering of the lens 3 by punching is described in the first embodiment.
This embodiment is the same as the first embodiment except that the rotation of the motor 21 is transmitted to the tool 11 via the belt 22 and the tool 11 is rotated during machining. After completion of the centering work, the stage 64 is moved backward.

According to the present embodiment, since the centering of the lens is performed while performing the measurement and applying the feedback, the centering can be performed with higher accuracy.

As a modification, in the present embodiment, similarly to the first embodiment, the outer periphery can be centered not only in a circle but also in an arbitrary shape. In this case, the inner shape of the tip processing portion of the tool 11 is an arbitrary shape that matches the desired lens outer shape after the centering operation, and the shape of the lens support member 50 is set even after the tool 11 punches out the lens 3. Shape should not interfere. The difference from the present embodiment is that centering is performed without rotating the motor 21. That is, punching is performed without rotating the tool 11 with respect to the lens 3. With the above configuration and operation, the lens can be centered in an arbitrary external shape in a short time. FIG. 5 to FIG. 8 are bottom views of the modified examples, respectively, in which the tip shape of the tool 11 is viewed from the side in contact with the lens.

[0028]

Embodiment 3 FIGS. 9 and 10 show this embodiment.
Is a front view in which a part is sectioned, and FIG. 10 is a side view of the lens. In this embodiment, only parts different from the above embodiments will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.

The lens supporting member 50a has a shape capable of receiving the flat portion of the lens 3a. The lens support member 50a is fixed on an XY stage 68 driven by motors 66 and 67. The XY stage 68 is mounted on the base 43.

In the present embodiment, the lens 3 having the optical axis formed perpendicular to the flat plate by using the apparatus having the above-described configuration.
Keep a in mind. In the centering operation, first, the lens 3a is placed on the lens supporting member 50a. Next, the paraxial eccentricity measuring unit 53 detects the amount and direction of the eccentricity of the lens 3a with respect to the ultrasonic processing unit 1. Therefore, the calculation unit 54 receives the measurement value of the paraxial eccentricity measurement unit 53 and issues a command to move the XY stage 68 in a direction to eliminate the amount of eccentricity to the motors 66 and 67.
Give to. The same operation is repeated to move the XY stage 68, adjust the optical axis position of the lens 3a, and center the lens 3a with respect to the tool 11.

Next, after lowering the ultrasonic processing unit 1 to bring the lens 3a into contact with the tool 11, a pressing force and ultrasonic waves are applied to the tool 11 in the same manner as in each of the above-described embodiments.
Cutting and punching. At this time, as is apparent from FIG. 9, the tool 11 and the lens supporting member 50a have a shape that does not interfere with each other when punching. During processing, the ultrasonic processing unit 1 is rotated by the motor 21 via the belt 22 to rotate the tool 11 to perform processing. The centered lens 3a is
It is dropped into the water tank 46 by the same operation as in each of the above embodiments, and the centering operation is completed.

According to this embodiment, centering can be performed even if the contact surface of the lens 3a with the lens supporting member 50a is not a curved surface but a flat surface.

As shown in FIGS. 11 and 12, a lens 3b having a plurality of optical axes formed on a flat plate perpendicular to the flat plate is provided.
Can be centered by the apparatus of this embodiment. In this case, the lens holder 50b functioning as a lens holding member
A support member is provided between the lenses 3b for reinforcement, which withstands the processing pressure at the time of processing. The tool 11 and the lens holder 50b do not interfere with each other when the lens 3b is punched out even if the support member is inserted.

The XY stage 68 is used not only for adjusting the optical axis position of each lens 3b but also for moving between the formed lenses. That is, after the centering of one lens is completed, the XY stage 68 is moved so that the next centering lens comes under the tool 11. With the above-described configuration and operation, centering can be performed by performing only one setup, even with a large number of lenses formed on a flat plate.

[0035]

As described above, according to the lens centering apparatus of the present invention, even if the outer diameter of the lens is large, the centering operation of the lens can be performed in a short time and with high accuracy. And the outer periphery of the lens is not limited to a circular shape,
Lenses can be centered in various shapes.

[Brief description of the drawings]

FIG. 1 is an exemplary conceptual diagram of the present invention.

FIG. 2 is a partially sectional front view showing the first embodiment.

FIG. 3 is a partially sectional front view showing a second embodiment.

FIG. 4 is a partially enlarged front view showing a second embodiment.

FIG. 5 is a bottom view showing a modification of the second embodiment.

FIG. 6 is a bottom view showing a modification of the second embodiment.

FIG. 7 is a bottom view showing a modification of the second embodiment.

FIG. 8 is a bottom view showing a modification of the second embodiment.

FIG. 9 is a partially sectional front view showing the third embodiment.

FIG. 10 is a side view showing a third embodiment.

FIG. 11 is a perspective view showing a modification of the third embodiment.

FIG. 12 is a partial front view showing a modification of the third embodiment.

FIG. 13 is a front view showing a conventional example.

FIG. 14 is a front view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ultrasonic processing unit 3 Lens 4 Centering unit 11 Tool

Claims (3)

(57) [Claims] 1. A lens centering device for centering an eccentric lens with respect to its optical axis and shaping the outer periphery to form a lens without eccentricity. An ultrasonic processing unit that provides a tool formed in a centering shape at the tip and longitudinally vibrates the tool, and an outer periphery of the eccentric lens is punched by a cylindrical tool provided in the ultrasonic processing unit. A lens support member for supporting the decentered lens so as to align the axis of a cylindrical tool provided in the ultrasonic processing unit with the optical axis of the lens supported by the lens support member. A unit for supplying loose abrasive grains to a processing portion of the cylindrical tool, wherein the cylindrical tool punches in the optical axis direction of the lens so as to form an outer periphery of the lens. Heart-up device of a lens according to claim. 2. The centering unit includes a lens moving mechanism, a paraxial eccentricity measuring unit, and a control unit that processes a signal from the paraxial eccentricity measuring unit to control the movement of the lens moving mechanism. The lens centering device according to claim 1, wherein 3. A lens centering device for centering an eccentric lens with respect to its optical axis and shaping the outer periphery to form a lens without eccentricity. An ultrasonic processing unit that provides a tool formed in a centering shape at the tip and longitudinally vibrates the tool, and an outer periphery of the eccentric lens is punched by a cylindrical tool provided in the ultrasonic processing unit. A lens support member for supporting the decentered lens so as to align the axis of a cylindrical tool provided in the ultrasonic processing unit with the optical axis of the lens supported by the lens support member. A unit for supplying loose abrasive grains to a processing portion of the cylindrical tool; and fitting the tool and the tool after punching an outer periphery of a lens in the optical axis direction of the lens with the cylindrical tool. I Lens heart-up apparatus characterized by comprising: a water tank for submerging the lens.