Fig. 1. (a) Time-domain intensity of white-light interference pattern and the meaning of the parameters; (b) linear relationship between the phase and the wave number in frequency domain

Fig. 2. Simulation results. (a) Surface profile of the sample to be measured; (b) coherence surface profile with error τ; (c) phase surface profile with local 2π phase jump; (d) final surface profile without any 2π ambiguity

Fig. 3. Elimination of local 2π phase jump. (a) Cross-sectional profile with 2π phase jump; (b) 2π phase-jump order between adjacent pixels; (c) final profile after removing local phase jump

Fig. 4. Experimental setup with a Mirau interference objective

Fig. 5. Surface profile measurement results of micro-spherical structure. (a) Coherence surface profile; (b) phase surface profile with local 2π phase jump; (c) final surface profile without phase ambiguity

Fig. 6. Surface profile measurement results of grating structure. (a) Coherence surface profile; (b) phase surface profile with local 2π phase jump; (c) final surface profile without phase ambiguity

Fig. 7. Cross-sectional profile of micro-spherical structure. (a) Cross-sectional profile of the coherence surface and the residual curve; (b) cross-sectional profile of the phase surface and the residual curve after removing 2π phase ambiguity

Fig. 8. Cross-sectional profile of grating structure. (a) Measurement result by white light interferometry; (b) step height measured by the stylus profiler (1 ?=0.1 nm)