Fig. 1. Principle of fringe compounding

Fig. 2. Principle of digital π phase shift. (a) Median points before and after interpolation; (b) symmetry transform and remove DC component

Fig. 3. Simulation of DFDM. (a) Measured object; (b) deformed composite fringe; (c) spectrum distribution; (d) low-frequency deformed fringe extracted via Filter 1; (e) high-frequency deformed fringe extracted via Filter 2; (f) extracted high-frequency Moiré fringe (sine); (g) extracted high-frequency Moiré fringe (cosine); (h) reconstructed result

Fig. 4. Spectrum analysis. (a1)-(d1) Spectrum distribution of different frequency fringes; (a2)-(d2) spectrum distribution after removing the DC of Fig. 4 (a1)-(d1)

Fig. 5. Experiment of DFDM. (a) Deformed composite fringe; (b) spectrum distribution; (c) low-frequency deformed fringe extracted via Filter 1; (d) high-frequency deformed fringe extracted via Filter 2; (e) spectrum distribution of AC component in Fig. 6(c); (f) extracted high-frequency Moiré fringe (sine); (g) extracted high-frequency Moiré fringe (cosine); (h) reconstructed face mask

Fig. 6. Comparison of results obtained by OMCGMP and DFDM. (a1) Deformed pattern using OMCGMP at low-frequency; (a2) deformed pattern using OMCGMP at high-frequency; (b) deformed pattern using DFDM; (c1) reconstructed result using OMCGMP at low-frequency; (c2) reconstructed result using OMCGMP at high-frequency; (d) reconstructed result using DFDM

Fig. 7. Error analysis of results measured using OMCGMP and DFDM. (a) Cutaway view at line 240 with Figs. 6(c1) and 6(d), and the reconstructed result obtained by 16-PSP; (b) cutaway view at line 406 with Figs. 6(c1) and 6(d), and the reconstructed result obtained by 16-PSP; (c) cutaway view at column 350 with Figs. 6(c1) and 6(d), and the reconstructed result obtained by 16-PSP

Fig. 8. Results of space-isolated objects reconstructed using DFDM. (a) Deformed composite pattern of space-isolated objects; (b) reconstructed result of Fig. 8(a); (c) cutaway view at line 345 with Fig. 8 (b) and the reconstructed result obtained by 16-PSP