Calibrated Phase-Shifting Digital Holographic Microscope Using a Sampling Moiré Technique

• Main Authors: Peng Xia, Qinghua Wang, Shien Ri, Hiroshi Tsuda
• Format: Article
• Language: English
• Published: MDPI AG 2018-05-01
• Series: Applied Sciences
• Subjects: digital holography; microscope; phase-shifting; Moiré technique
• Online Access: http://www.mdpi.com/2076-3417/8/5/706

A calibrated phase-shifting digital holographic microscope system capable of improving the quality of reconstructed images is proposed. Phase-shifting errors are introduced in phase-shifted holograms for numerous reasons, such as the non-linearity of piezoelectric transducers (PZTs), wavelength fluctuations in lasers, and environmental disturbances, leading to poor-quality reconstructions. In our system, in addition to the camera used to record object information, an extra camera is used to record interferograms, which are used to analyze phase-shifting errors using a sampling Moiré technique. The quality of the reconstructed object images can be improved by the phase-shifting error compensation algorithm. Both the numerical simulation and experiment demonstrate the effectiveness of the proposed system.