Phase-shifting characteristics of refractive index change-based phase-shifting interferometer for optical imaging applications

Abstract

We present spectral characteristics of the phase shifts in refractive index based phase-shifting interferometer. The conventional mechanical movement method cannot provide the same phase change for different wavelengths, which occurs phase information distortion in the incoherent interferometer. The refractive index-based phase-shifting method can adjust the uniform phase shift over a wide spectral window. Spectral phase-shifting errors of the proposed method were compared with those of the mechanical phase-shift method. The proposed method can be applied to eliminate unwanted phase-shifting errors and to obtain correct phase information of optical tomographic images.