3D measurement method based on S-shaped segmental phase encoding

Abstract

Phase-based encoding has good immunity and robustness due to its insensitivity to ambient light, camera noise, and surface reflectance of measured objects. However, the number of code words is limited using traditional phase encoding method. In order to solve this problem, this paper proposes a new approach named S-shaped segmental phase encoding for 3D measurement. Specifically, by using a segmentation mechanism, the proposed method can, firstly, expand the range of code words whose number is limited using traditional phase encoding method. Secondly, the measurement accuracy can be improved. In this paper, Gray code is used to encode the phase encoding segment number, such that the fringe order judgment accuracy can be guaranteed. The experimental results demonstrated more accurate and efficient 3D shape measurement than the traditional methods, especially regarding the measurement of complex and isolated objects.