Fig. 1. Optical path of the measurement system

Fig. 2. Flow chart of the surface recovery algorithm

Fig. 3. Flow chart of the PTI iteration process

Fig. 4. Simulation data. (a) Scanning position; (b) scanning deviation; (c) white light interferometric signal

Fig. 5. Calculation result of PTI. (a) Curves of the calculated scanning position and the real scanning position; (b) errors of calculation

Fig. 6. Calculation results of the simulated step. (a) 3D topography; (b) 1D profile; (c) residual of 1D profile

Fig. 7. Interferogram of the experiment. (a) White light interferogram; (b) monochromatic light interferogram

Fig. 8. Result obtained from the monochromatic light interferogram. (a) Scanning position; (b) scanning deviation

Fig. 9. Topography of the step calculated by different methods. (a) Measurement without vibration; (b) DVSI; (c) HDVSI; (d) WLPSI

Fig. 10. Comparison of measurement results of 1D profile. (a) White-light interferogram; (b) horizontal profile; (c) vertical profile

Fig. 11. Deviation of different parameters. (a) Average height; (b) R_a; (c) R_q