High-Accuracy Surface Profile Measurement Based on the Vortex Phase-Shifting Interferometry

Table 1

Error comparison of the nonlinear modulation with different gamma values.

	0.6	0.8	0.9	1.1	1.3	1.5	1.8	2
ΔPhase_max (rad)	0.047	0.017	0.0076	0.0065	0.0188	0.031	0.053	0.071
ΔLength_max (nm)	9.57	3.46	1.55	1.32	3.83	6.32	10.80	14.46
Error rate_max (%)	47	17	7.6	6.5	18.8	31	53	71