Fig. 1. Real-time measuring system of PMP based on four-grayscale fringe pattern projection

Fig. 2. Projection and capturing of four-grayscale encoded fringe pattern. (a) Fringe pattern projection matrix; (b) grayscale distribution of fringe pattern projection; (c) capturing of reference fringe; (d) capturing of deformed fringe

Fig. 3. OPE on periodic boundary of fringe pattern. (a) Gray-scale distribution on periodic boundary of fringe pattern; (b) inaccurate segmentation of fringe pattern

Fig. 4. Periodic boundary searching of fringe patterns. (a) Gray value of fringe pattern; (b) gray differential of fringe pattern

Fig. 5. Flow chart of fringe segmention

Fig. 6. Binary fringe patterns with 1/3 period displacement after fringe segmentation. (a) 1st frame of binary fringe pattern; (b) 2nd frame of binary fringe pattern; (c) 3rd frame of binary fringe pattern

Fig. 7. Schematic of experimental setup

Fig. 8. Measuring experiment for knife. (a) Knife; (b) captured deformed fringe pattern; (c) binary deformed fringe pattern after segmentation; (d) extracted sinusoidal deformed fringe patterns; (e) wrapped phase; (f) 3D reconstructed result

Fig. 9. Real-time measuring experiment for workpiece. (a)(b)(c) Four-grayscale deformed fringe patterns captured with 0.03 s period; (d)(e)(f) corresponding wrapped phases; (g)(h)(i) corresponding reconstructed results

Fig. 10. Face-model reconstruction experiment. (a) Reconstruction result of FTP; (b) reconstruciton result of proposed method; (c) reconstruction result of 3-step PMP; (d) cross section of 670th column; (e) details of nose tip