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

<div>Interference patterns of +1 order vortex light and plane light. (a)–(d) Interferograms before placing the sample, and the phase of vortex light is (a) 0, (b) <i>π</i>/2, (c) <i>π</i>, and (d) 3<i>π</i>/2. (e)–(h) Interferograms after placing the sample, and the phase of the vortex light is (e) 0, (f) <i>π</i>/2, (g) <i>π</i>, and (h) 3<i>π</i>/2.</div>

International Journal of Optics

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Figure 7

Figure 7: High-Accuracy Surface Profile Measurement Based on the Vortex Phase-Shifting Interferometry 