Lensless Fourier transform digital holography with optical fiber based on spatial light modulator

We proposed a novel method of using homogeneous-type nematic liquid crystal spatial light modulator (SLM) to electronically control the modification of reference beam in lensless Fourier transform digital holography (LFDH). By using nematic liquid crystal SLM as a phase-shifting device, which provides the advantage of avoiding any mechanical adjustments, the four-step phase-shifting technology can be realized availably. Furthermore, a convenient experimental setup for recording object in LFDH is presented. Almost perfect spherical reference wave can be acquired by using optical fiber, and the algorithm of median filtering is successfully employed in image processing to improve the quality of the reconstruction image.