Fig. 1. Batwing effect in profile of step-type microstructures measured by white light interferometry

Fig. 2. Subpixel subdivision algorithm for integer pixel unit

Fig. 3. Step edge located at different subpixel positions. (a) Three-dimensional diagram of step sample; (b) top view of step sample

Fig. 4. Profile in x-axis direction when step edge is located at different subpixel positions

Fig. 5. Step sample view on pixel array of CCD target surface. (a) Three-dimensional diagram of step sample; (b) top view of step sample

Fig. 6. Step topography of simulation recovery results. (a) Side view; (b) sampling line in y-axis direction; (c) sampling line in x-axis direction

Fig. 7. Test sample and experimental diagram of area with 6 μm linewidth. (a) Diagram of RSN calibration plate; (b) measured interference fringe patterns

Fig. 8. Topography recovery results in a single cycle of RSN calibration plate

Fig. 9. Profile recovery results and wavelet coefficients on step edge sampling line. (a) Left edge; (b) right edge

Fig. 10. Linear fitting results of key pixel points. (a) Left edge; (b) right edge

Fig. 11. Different step heights corresponding to non-ideal vertical edges

Fig. 12. Relationship between measurement uncertainty and inclination angle φ