High-accuracy simultaneous phase extraction and unwrapping method for single interferogram based on convolutional neural network

Abstract

The high-precision dynamic measurement of optical surfaces in unstable environments is a critical problem in the process of fabrication and application. In order to solve this problem, a high-precision ultra-fast phase demodulation method based on convolutional neural network is proposed in this paper. The wrapped phase and corresponding wrap count map can be obtained from one interferogram at the same time, so the phase extraction and unwrapping are performed simultaneously. It only takes 0.02 seconds to demodulate single-frame interferogram. Simulation and experimental results show that the root-mean-square error between this algorithm and phase-shifting algorithm is better than 0.01λ (λ=632.8nm). It indicates that the proposed method has excellent performance in measurement accuracy and efficiency.