SU853382A1 - Optical electronic devie for measuring angular diaplacement of an object - Google Patents

Description

one

The invention relates to instrumentation engineering and is intended to measure the angular displacement of objects.

A photoelectric autocollimator for determining the angular position of an object is known, which contains a light source, a lens, a translucent mirror, a slit diaphragm, a modulator, an autocollimator with a mirror mounted on the object being monitored, a photodetector, a narrow-band amplifier, a phase detector and a sinusoidal voltage generator ij.

The disadvantages of this autocollimator are the small range of measuring angles, the dependence of the accuracy of measuring the angle on the distance to the object and on the radiant power of the light source, the impossibility of using such devices under the conditions of vibrations and overloads.

The closest technical solution to the invention is an optoelectronic device for measuring the angular displacement of an object, containing a radiation source, an autocollimator consisting of successively installed light emitting diodes from the radiation source.

a cube, a lens, in the same focal plane of which the radiation source is located, and a flat mirror fastened with the object, a photo-recording system installed at the radiation output from the autocollimator in another focal plane of the lens optically conjugated to the first, and the electronic unit

10 signal processing photodetector 2.

The disadvantages of this device are the drift of zero due to the action of extraneous sources of illumination of the photodetector, the effect on the accuracy of 15 measurements of the angular displacement of an object of temporary instability of the parameters of the photodetector, a small range of measured angles, the dependence of the accuracy of measurement of angles on the distance between

20 controlled object and measuring device.

The purpose of the invention is to improve the accuracy of measuring the angular displacement.

This is achieved by the fact that the source

25 radiation is made in the form of a ruler of evenly spaced discrete emitters pairwise symmetrical about the optical axis of the device, with a total number of emitters

30 big two, and photo registrar 11tsg1I

The system is designed as two photodetectors, also symmetrically located with respect to the optical axis of the device.

The drawing shows a schematic diagram of the device.

The device contains a radiation source 1, made in the form of a ruler of evenly spaced discrete emitters pairwise symmetrical with respect to the optical axis of the device, with a total number of emitters greater than two, an autocollimator consisting of a beam-splitting 2, objective 3 and a mirror 4 attached to the object under study, photo registration system the two of the photodetectors 5 and 6, and the electronic unit 7 signal processing photodetectors,

The device operates as follows. When the direction of the normal of the mirror 4 and the optical axis of the autocollimator coincides in the plane of the photodetectors 5 and b, an image of the radiation source 1 is constructed, and this image turns out to be siaf etrich relative to the optical axis. Thus, on the sensitive sites of both photodetectors 5 and 6, the same number of images of discrete emitters of radiation source 1 is located, and alternately switching discrete emitters of radiation source 1 from photoreceivers 5 and b, the same number of pulses is taken, equal to the number of images of discrete emitters caught in photodetector 5 and b. Unit 7 counts and compares the number of pulses taken from the photodetectors 5 and 6. Without the angular mismatch of the mirror 4, the number of pulses taken from the photo receivers 5 and b during the switching period of all emitters is the same.

With the angular mismatch of the mirror 4, the image of the center of the radiation source symmetry is shifted from the optical axis and the equality of the number of images of the discrete emitters of the radiation source 1 to the photodetector 5 and b is violated.

In this connection, a different number of pulses is taken from the photodetectors 5 and b. The difference in the number of pulses indicated during the switching period is detected by block 7 and is proportional to the magnitude of the angular mismatch.

Thus, the sensitivity and accuracy of this device does not depend on the distance between the device lens and the mirror, as well as the background illumination, and with an appropriate choice of the step of the discrete emitters and the focal length of the lens can be made quite high.

Claims (2)

Invention Formula Opto-electronic device for 5 measuring the angular displacement of an object, containing a radiation source, an autocollimator., Consisting of successively installed radiation from a radiation source of a light-absorbing cube, a lens, in the same focal plane of which the radiation source is located, and a flat mirror attached to the object, photo registration system mounted at the output of the radiation from the autocollimator in another focal plane of the lens optically coupled to the first, and the electronic unit for processing the signal of the photodetector, about aphid In order to improve the accuracy of measuring the angular displacement, the radiation source is made in the form of a ruler of evenly spaced discrete emitters pairwise symmetrical about the optical axis of the device, with a total number of emitters greater than two, and the photo registration system is made in the form of two photodetectors, also symmetrically located 0 relative to the optical axis of the device. Sources of information taken into account in the examination of f 1. Torochkov V.Yu. and others. A photoelectric autocollimator with a small constant time. - Optical-mechanical industry, 1976, 5, p. 26  2. Lepkov G.A., Lokhmatov A.I. and Sosnovsky M.G. Autocollimator with photoelectric reading. - Measuring equipment, 1963, No. 8, p. 25 (prototype).