A novel fast 3D measurement method based on phase-coded fringe projection

Fringe projection profilometry is widely used for the 3D measurement of real-world objects; however, quickly obtaining high-precision 3D measurements is an issue that needs to be resolved. Therefore, a novel fast 3D measurement method based on phase coding is proposed in this paper. It involves an unconstrained fast phase unwrapped method that can solve the absolute phase with only four fringe patterns and does not require any pre-acquired object information. This method uses the special relationship between one coded fringe pattern and the three other phase-shifting fringe patterns to achieve an unwrapped phase. To ensure higher measurement accuracy, a special coding sequence is designed to improve the projection frequency in the coding stage (0, pi), which not only increases the number of code words, but also effectively improves the decoding accuracy. The high-speed and high-accuracy performance of the proposed method is successfully verified through simulations and experimentation, verifying its future applicability in the field of rapid measurement.