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Parallelism measurement of spatially separated optical axes using a quadriwave lateral shearing interferometer
Bing-Jie Wang1,2, Xing-He Li3, Xue-Yuan Li1
1MOE Key Laboratory of TianQin Mission, TianQin Research Center for Gravitational Physics & School of Physics and Astronomy, Frontiers Science Center for TianQin, Gravitational Wave Research Center of CNSA, Sun Yat-sen University (Zhuhai Campus), Zhuhai 519082, China.
Abstract:
Parallelism measurement of optical axes is essential for many optical systems. Conventional collimators are limited by their aperture size and suffer from reduced accuracy when nearly parallel optical axes produce overlapping focal-plane spots. In this paper, we present a convenient method for measuring optical-axis parallelism using a quadriwave lateral shearing interferometer (QWLSI), without being fundamentally limited by its aperture. Two 1064 nm beams are used to validate the method, and their direction angles are measured simultaneously. Experimental results show a measurement resolution of 1.08 ' ' and an angle measurement accuracy of1.63 ' ' .
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