High-precision capacitance-type displacement sensor for direct non-contact detection of mirror surface high-low difference

Abstract

The invention relates to a high-precision capacitance-type displacement sensor for direct non-contact detection of mirror surface high-low difference. All sub-mirror surfaces to be detected are mounted on a girder of a support system; the girder of the support system is provided with a reference plate; a capacitance polar plate is mounted on one side of the reference plate opposite to the sub-mirrors and corresponding to the sub-mirror surface; besides, a reflection metal film layer or a metal mirror surface body of the corresponding sub-mirror surface to be detected is used as the other polar plate of the capacitor; and the two capacitance polar plates are connected with a detection circuit of the capacitance displacement sensor. The invention can directly realize detection of the high-low difference of spliced mirror surfaces and has the advantages of clear principle, compact structure, simple process, high detection precision of the high-low difference, and the like. Compared with the traditional classical sensor, the sensor can directly obtain the mirror surface high-low difference in a non-contact way without introducing other stray light. The invention is suitable for the high-low difference detection of the mirror surfaces of optics or radio systems.

Description

Technical field [0001] The invention relates to a high-precision capacitive displacement sensor for non-contact direct detection of splicing mirror height difference, which is used especially for realizing splicing astronomical telescope mirror height difference detection (including optical system requirements for confocal and common phase, or even large For batch use). Background technique [0002] High-precision sensor technology is an inevitable choice for the development of science and technology. There are many common sensors that can be used to detect the height of the mirror surface when splicing the mirror surface of the astronomical telescope. They are mainly divided into contact type and non-contact type, direct detection type and indirect detection type, etc.; contact type mainly includes capacitors installed on the back or side of the mirror Displacement sensors such as, inductance, eddy current, etc., through pre-calibration to detect the height of the mirror; non-c...

AI Technical Summary

Problems solved by technology

[0003] The above-mentioned multiple methods and the displacement sensors realized by them all have various disadvantages.

Contact measurement is to install a displacement sensor on the back or side of the mirror, and it is often necessary to use other instruments to calibrate the high and low position of the sensor, such as Keck telescope splicing the main mirror, etc.; although the optical fiber displacement sensor can directly reflect the height of the mirror, but because it uses optical energy Detection, so it will bring stray light and other factors to the optical system. In addition, the distance between the fiber end face and the mirror surface will affect the measurement accuracy; the pupil plane detection and image plane detection methods based on the optical detection system will be affected by atmospheric turbulence and temperature changes. Influenced by changes in various environmental factors such as , noise, etc., the accuracy is limited and the detection batch is limited, and the use occasions are limited

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