Digital holographic microscopy (DHM) well-known method allowing three-dimensional phase information and amplitude information of sample to be simultaneously observed. In DHM, holographic interference pattern generated by superposition of sample beam and reference beam is recorded by CCD camera, and the optical field of sample is numerically reconstructed by post processing based on diffraction theory. DHM can be applied in many optical measurement fields such as deformation observation, vibrational analysis, and biomedical imaging.