Aspheric lens computer-generated holography interference detecting method based on liquid crystal spatial light modulator

Abstract

The invention discloses an aspheric lens computer-generated holography interference detecting method based on a liquid crystal spatial light modulator and relates to the field of optical measurement. According to the method, online detection of an aspheric reflector is achieved by a computer-generated holography interference method by the aid of a digital phase-shifting interferometer used for providing a light source, an imaging system and interferogram analysis software and by means of introducing the liquid crystal spatial light modulator to serve as a computer-generated holography carrier. A zero compensation lens is introduced into a testing light path to compensate spherical aberration of the aspheric lens, residual wave aberration is obtained by ZEMAX ray tracing, a mathematical model of the residual wave aberration is obtained according to a Zernike coefficient and a Zernike expression of the wave aberration and is made into a computer-generated hologram by means of computer-generated holography encoding, the computer-generated hologram is loaded on the liquid crystal spatial light modulator and forms reference light after being modulated, and the reference light interferes with testing light. The method can achieve real-time online detection of the aspheric lens by the aid of a powerful interferogram analysis function of the digital phase-shifting interferometer and a real-time computer-generated hologram display function of the liquid crystal spatial light modulator.

Description

technical field [0001] The invention relates to the field of optical measurement. Background technique [0002] Aspherical optical elements are widely used in astronomy, aviation, aerospace, military, industrial, medical and other fields due to their good optical properties such as eliminating various aberrations, reducing light energy loss, and obtaining high-quality images. The extensive use of aspheric mirrors has led to a rapid increase in the processing requirements of aspheric optical components, but the level of aspheric surface detection technology is a key factor that restricts the wide application of aspheric mirrors. Therefore, research on aspheric surface detection technology has become a hot spot in the field of modern optical measurement. question. Computational holographic interferometry is currently the main way to detect aspheric surfaces due to its advantages of high measurement accuracy and high sensitivity. [0003] Invention patent CN 102519392 A "A fu...

AI Technical Summary

Problems solved by technology

[0005] The present invention aims to solve the problems of long processing period, high processing cost and inability to realize the on-line detection of the aspheric surface processing process of the optical hologram; the problem that only the shallow aspheric surface can be measured by simply using a digital phase-shift interferometer; and the existing There are many optical elements in the aspheric surface detection device, it is difficult to adjust the optical path, the light energy attenuation is large, and the analysis of the interferogram is difficult. A holographic interferometric detection method based on the aspheric mirror of the liquid crystal spatial light modulator is proposed.

Images