Removal of non-diffraction wave in optical-path-length-shifting digital holography

We propose an algorithm for extracting the image of an object from the reconstructed image in the in-line digital holography using two holograms reported by Y. Zhang. In the proposed algorithm the non-diffraction wave can be analytically calculated by using the intensity of the reference wave and be removed from the reconstructed image. We confirmed the validity of the proposed algorithm by numerical results. In comparison with the algorithm reported by Zhang, it was found that the proposed algorithm reduced the errors down to 1/5 and 1/3 in amplitude and phase by the simulation, respectively when the ratio of the amplitude of the reference wave to that of the object wave was 4. Thus, if have been confirmed that the digital holography employing the proposed algorithm have be suitable for high-precision three-dimensional image capturing and measurement.