Precise Interferometry System for Dynamic Measurements Employing Phase Modulation Style Spatial Light Modulator

Abstract

This paper presents an interferometry system that incorporates a phase modulation type spatial light modulator (SLM) to enable high-precision dynamic measurement. The system includes a unit for generating mutually orthogonal linearly polarized reference and testing lights, a phase modulation type SLM, an interferometer, and a light detector. The SLM, consisting of multiple pixels with specific phase distributions, modifies the spatial phase distribution of the light waves. The interferometer utilizes modulated and unmodulated lights to perform interferometry, producing coherent light that is then detected by the light detector. Furthermore, the pixels of the SLM correspond to the pixels of the light detector, ensuring accurate measurement. This system facilitates measurement across multiple spatial carriers and enables high-precision dynamic measurement. Additionally, the paper introduces a spatial phase-shifting unit and a liquid crystal spatial light modulator phase-correcting unit.