JPH0696207B2 - Optical element position adjustment method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a lens, a mirror, etc. supported by an elastic support, such as when a lens of a camera is supported by a support which is an elastic member. The present invention relates to a fine position adjusting method for an optical element that adjusts the relative position of an object to be adjusted such as an optical element.

[Prior Art] At present, in a factory or the like, for example, when a lens is attached to a frame of a camera, it is necessary to finely adjust the inclination of the lens to align the axes. Position adjustment for the purpose of matching the relative positions of two or more parts to a desired position is often necessary. However, an object to be adjusted of an optical element such as a lens or a mirror is often supported by an elastic body such as a spring member, which makes fine adjustment difficult. In other words, because the frictional force acts between the object to be adjusted and the support, even if an external force is applied to bring the object to be adjusted into a predetermined position, the support itself will undergo elastic deformation and deflection, and the force applied Except for, there was some backlash that caused the adjusted object to return to its original state.
In addition, stick-slip occurred due to variations in the surface condition of the contact portion and the bonding force.

To solve such a problem, conventionally, the amount of backlash when the external force is removed from the amount of movement of the object to be adjusted by the external force is estimated, and the external force is applied in consideration of the amount of backlash in advance. That is, the object to be adjusted is located at a point exceeding the target value when the external force is applied. The fine position adjustment is performed by repeating such an operation several times.

[Problems to be Solved by the Invention] However, in the conventional method, the same operation must be performed several times, and when the target point is exceeded, the same operation must be performed from the opposite direction. Furthermore, problems such as stick-slip have not been solved yet. Therefore, there are problems that it is difficult to adjust the fine position and it takes time.

[Means for Solving the Problem] In the present invention, as a means for solving the problem that the fine position adjustment is difficult due to the backlash, the stick slip and the like as described above, in the present invention, the vibrator is slightly vibrated and its vibration is reduced. The object to be adjusted is provided by transmitting it to the object to be adjusted.

In particular, the present invention holds an optical element on a bar member extending in the optical axis direction, and fits one end side of the bar member on a collar member elastically supported by a fixed holding member, and the other end side of the bar member. Is configured to be supported by a holding member as a fulcrum, a vibrator is brought into contact with the one end side of the bar member, and the bar member is pressed by the vibration of the vibrator, so that the other end side of the bar member is fixed. A method for adjusting the position of an optical element, which comprises displacing the position of the optical element by displacing the fulcrum support, measuring the position of the displaced optical element, and adjusting the position of the optical element by the operation. I will provide a.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a detailed view of the present invention, which relates to the fine adjustment of the lens angle of the camera. Reference numeral 1 in the figure is a vibrator for generating vibration, and a current flows by turning on the following switching circuit. When the current flows, the vibrator is in an extended state. Also, when the switching circuit is turned off, the oscillator is in a contracted state. That is, the switching circuit is turned on,
The oscillator vibrates by repeatedly turning off. Reference numeral 2 is a bit for transmitting vibration from the vibrator, and 3 is a support base of the vibrator 1. Reference numeral 4 is a slide table for positioning the vibrator 1, and 5 is a motor for driving the slide table 4 in the vertical direction.

The slide table 4 moves in accordance with the forward / reverse rotation of the motor 5, thereby moving the vibrator 1 forward and backward in the axial direction.

Thereby, the feeding amount of the bit 2 at the tip of the vibrator is adjusted.

Reference numeral 6 is a lens bar which is an object to be adjusted. 6A is a lens and is integrated with the lens bar 6.

6B is a lens bar support fixed to the lens frame 13 and is formed by molding.

6D is a support collar that is an adjustment collar on which the lens bar 6 is fitted.
A wave washer 6C is provided between 6B and the adjusting collar 6D, and the adjusting collar 6D is movable relative to the lens bar 6B in the direction perpendicular to the axis. In addition, the tip of the vibrator 1 is in contact with the adjustment collar 6D during adjustment.
Is transmitted to the lens bar 6 via the adjusting collar 6D. 6E is an angle measuring mirror which is integrated with the lens bar 6 and is held in parallel with the lens 6A by the optical element holding member 14.

The holding member 14 has a ring shape, and has a protrusion 14A for fixing the lens bar 6 on the outer peripheral surface thereof.

A fulcrum pin 14B is planted in the protrusion 14A, and the fulcrum pin 14B is
Is the cam portion of the cam member 15 mounted inside the frame 13.
It is in contact with 15A. Reference numeral 6F indicates a pin 14B and a cam portion 15A.
Shows the fulcrum of.

Reference numeral 16 in the drawing denotes a fitting portion between the center hole of the cam 15 and the lens bar 6. A control circuit 7 controls the operation of the motor 5. A collimator 8 has a built-in half mirror. 9
Is an A / D converter that converts an analog value measured by the comimeter 8 into a digital value. Reference numeral 10 is a power source for the vibrator, and 11 is a switching circuit for vibrating the vibrator 1. Reference numeral 12 is a central processing unit (CPU) that processes the values from the A / D converter 9 and the switching circuit 11.

Next, the operation of the above configuration will be described. First, by turning on a power source (not shown), the following operation becomes possible. Next, the vibrator power supply 11 is turned on to keep the vibrator extended. Next, in the collimator 8, light is emitted from the rear part of the built-in half mirror, passes through the half mirror, and illuminates the mirror 6E. The reflected light reflected by the mirror 6E returns to the collimator 8 again. Then, this time, it is reflected by the half mirror, and the chart by the reflected light is measured. Lens depending on the measured chart position
You can see how much 6A and mirror 6E are tilted. The measured value is sent to the A / D converter 9 and becomes a digital value. The value is taken into the central processing unit 12, and the amount of movement of the slide table 4 to a predetermined position is calculated based on the value. Based on the calculated movement amount, the motor 5 is rotated through the motor control circuit 7 to move the slide table 4, and the tip of the vibrator 1 is adjusted to the adjustment collar 6D.
Press to position the lens bar 6 so that it is at the position where the adjustment was completed. Here, the vibrator is first stretched, but this is to prevent overshoot of the adjustment value due to vibration. That is, if the positioning is performed in this way, the lens bar 6 will not exceed the adjustment end scheduled position no matter how much vibration is applied. Further, in the positioned state, the lens bar 6 is apparently at the adjustment end position, but the adjustment collar 6D is elastically deformed, and if the vibrator 1 is removed, the lens bar 6 will return somewhat upward. Next, the vibration of the vibrator 1 is started by the switching circuit 11 to move and adjust the lens bar 6 through the adjusting collar 6D. As for how to vibrate at this time, generally the external force applied is represented by f = ma, f: external force, m: mass of adjusting machine side bit, and a: acceleration of m. If the external force is small, when the adjustment collar 6D is subjected to a force due to the frictional force between the adjustment collar 6D and the wave washer 6C and between the wave washer 6C and the support 6B, the support 6B, which is an elastic body, is deformed. Resulting in. Therefore, when the external force applied by the vibrator 1 is removed, the support base 6B is deformed during that time. Therefore oscillator 1
When the external force applied by the
The lens bar 6 is returned by the amount that 6B was deformed. Therefore, the external force f is increased. When the external force f is increased, the influence of frictional force is almost eliminated. To increase the external force f, the acceleration a must be increased.
That is, it is necessary to increase the vibration frequency or increase the vibration amplitude. However, if the vibration amplitude is increased, the displacement due to stick-slip increases, and precise alignment cannot be performed. That is, the vibration amplitude must be made as small as possible, and therefore the vibration frequency must be increased to increase the acceleration a. After all, as a method of vibrating the vibrator 1, it is sufficient to vibrate it with a small amplitude and a high frequency. Further, in order to achieve a highly efficient state, it is desirable that the object to be adjusted is vibrated at the same frequency as the adjustment direction fn (natural frequency) and in the opposite phase.

After that, the lens bar 6 and the adjusting collar 6D, which are vibrated by the vibrator 1, relatively move with 6B, and the right ends of the lens bar 6 and the collar 6B slightly move downward. Therefore, the lens 6A integrated with the lens bar 6 has a fulcrum 16 of the lens bar 6.
Tilt upward with a slight angle. Color with 16 as a fulcrum
The lens bar 6 tilts as the 6D moves, and the lens 6A
And the mirror 6E will tilt. Thereafter, the switching circuit 11 stops the vibration of the vibrator 1 and raises the slide table 4. Then, the collimator 8 again applies light and the measured value is confirmed. If the measured value is within the allowable range, the adjustment ends. If it is outside the allowable range, the above process is repeated again.

In this embodiment, the position adjustment of the lens of the camera is shown, but any other fine position adjustment using an elastic member as a support can be used.

Further, although the slide table is used in this embodiment, it is not always necessary to use the slide table because of the adjustment system and the adjustment stroke.

Further, although the position is adjusted in the vibration direction of the vibrator in the present embodiment, it can also be used for position adjustment in the direction perpendicular to the vibration direction and other directions as shown in FIG. However, the third
In the figure, the X direction is the vibration direction and the Y direction is the adjustment direction.

In this embodiment, the vibration direction is only the vertical direction,
By combining a plurality of vibrators, it is possible to perform planar adjustment and three-dimensional adjustment.

[Effects of the Invention] As described above, by performing fine position adjustment using the vibrator, the backlash amount can be reduced by increasing the vibration frequency, and the vibration amplitude can be reduced. Stick-slip can be reduced.
As a result, the adjustment time can be shortened and the accuracy can be improved.

[Brief description of drawings]

FIG. 1 is a detailed view of an embodiment of a fine position adjusting mechanism,
FIG. 2 is a detailed view of a portion A in FIG. FIG. 3 is a view showing a modification of the contact portion between the vibrator and the member to be adjusted in FIG. 1: Transducer, 2: Adjustment bit, 3: Support stand 4: Slide table, 5: Motor 6: Object to be adjusted, 7: Motor control circuit 10: Oscillator power supply, 11: Switching circuit 12: Central processing unit (CPU)

Claims (1)

[Claims] 1. A bar member extending in the optical axis direction holds an optical element, and one end side of the bar member is fitted to a collar member elastically supported by a fixed holding member, and the other end side of the bar member is mounted. Is configured to be supported by a holding member as a fulcrum, a vibrator is brought into contact with the one end side of the bar member, and the bar member is pressed by the vibration of the vibrator, so that the other end side of the bar member is fixed. A method for adjusting the position of an optical element, which comprises displacing the position of the optical element by displacing the fulcrum support, measuring the position of the displaced optical element, and adjusting the position of the optical element by the operation. .