Phase Error Analysis and Correction for Crossed-Grating Phase-Shifting Profilometry

Phase Error Analysis and Correction for Crossed-Grating Phase-Shifting Profilometry

Blog Article

Crossed-grating phase-shifting profilometry (CGPSP) has great utility in three-dimensional shape measurement due to its ability to acquire horizontal and vertical phase maps in a single measurement.However, CGPSP is extremely sensitive to the non-linearity effect of a digital fringe projection system, which is not studied in depth yet.In this paper, a chocolate chip cookie purse mathematical model is established to analyze the phase error caused by the non-linearity effect.Subsequently, two methods used to eliminate the non-linearity error are discussed in detail.To be specific, a double five-step algorithm based on the mathematical model is proposed to passively suppress the second non-linearity.

Furthermore, a precoding gamma correction method based on probability distribution function is introduced to actively attenuate the non-linearity of the captured crossed fringe.The comparison results show that the active gamma correction method requires less fringe patterns and can more effectively reduce the non-linearity error compared with the passive method.Finally, employing neflintw-r6mpw CGPSP with gamma correction, a faster and reliable inverse pattern projection is realized with less fringe patterns.