Dynamic Digital Wavefront Interference Measuring Method Based On SLM

With the advancement of technologies such as photoelectric detection,image processing,precision machinery,and computers,modern optical testing technology has been greatly developed.In the detection of precision optical components and optical systems,interferometers are currently more effective high-precision detection methods.The dynamic interferometer can collect multiple interferograms at different spatial positions at the same time to reconstruct the shape of the measured wave surface to achieve high-precision measurement.At the same time,the dynamic interferometer has strong anti-vibration ability,which can eliminate the influence of atmospheric turbulence and environmental disturbance on detection.After years of research,dynamic interferometers have become one of the research hotspots in the field of optical measurement in recent years.This thesis studies the digital wavefront dynamic interference technology,and researches and analyzes its key technology.In order to accurately and conveniently obtain the four phase-dependent light intensity parameters,the Jones matrix is used in this paper to analyze the principle and implementation of SLM-based digital wavefront dynamic interference testing.Based on this,a complete SLM-based digital wavefront dynamic interference device scheme is proposed.The related algorithms are specifically written,and the planar optical elements are simulated and analyzed.The phase modulation characteristics of SLM for spherical optical element dynamic interference test and the principle of testing for aspherical optics are studied.Due to the spatial non-uniformity of the liquid crystal backplane in the liquid crystal spatial modulator,the aberration term introduced by the incident wavefront,and correcting this aberration is very important to improve the phase modulation accuracy of the liquid crystal spatial light modulator.This paper proposes a method for measuring the phase modulation characteristics of a liquid crystal spatial light modulator.The phase modulation accuracy of the liquid crystal spatial light modulator is calibrated using a Fizeau interferometer,linear correction is performed using inverse interpolation,and finally SLM phase modulation accuracy is corrected Calibration and compensation.The linear correlation of the corrected phase modulation curve can reach 0.9987,and the correction error is 0.13.In addition,the experimental verification of the dynamic interference test method is provided in this paper,which provides technical accumulation and theoretical reference for the study of dynamic interferometers,which is of great significance in practical engineering applications.