Dual-wavelength generalized phase-shifting interferometric imaging

Aiming at some common problems of the current dual-wavelength multi-step phase-shifting interferometric imaging method, a dual-wavelength generalized phase-shifting interferometric imaging method is proposed in this work. In this method, the phase shift can be any value within (0, ), which need not be a special value or a known value, and the introduced phase shift of two wavelengths is independent of each other. By calculating the difference between each two phase-shifted interferograms and the Hilbert transform values, the introduced phase shift can be calculated, and then the wrapped phase distribution at a single wavelength can be calculated, and finally the continuous phase under the synthetic wavelength can be obtained. Then through a series of simulation, the effectiveness and feasibility of this method are confirmed. Finally, it is concluded that proposed method can not only quickly process open straight stripes, but also process closed circular stripes, and have very high accuracy and excellent phase recovery effect.