Deep learning-based single-shot absolute phase retrieval using a triangular-wave embedded fringe coding strategy

Abstract

In the field of 3D measurement, fringe projection profilometry attracts the most interest due to its high precision and convenience. However, it is still challenging to retrieve the unambiguous absolute phase from a single fringe image. In this paper, we propose a deep learning-based method for retrieving the absolute phase of triangular-wave embedded fringe images. Through the learning of a large amount of data, we use two neural networks to obtain high-precision wrapped phase and coarse absolute phase from the triangular-wave embedded fringe images respectively so as to obtain accurate fringe order. Combining the wrapped phase and fringe order, we can obtain high-precision absolute phases. The experimental results demonstrate that compared with our previous proposed composite dual-frequency fringe coding strategy, the fringe image of the new triangular-wave embedded fringe coding strategy as the input of the network can obtain the absolute phase with higher accuracy.