Optics and Photonics Society of Iran

Interferometric microscopes are one of the most effective methods in study of micron and sub-micron sized samples including biological cells. Among the different interferometric methods, digital holographic microscopy (DHM) has a significant importance in studying the dynamics of moving samples. Recently the utilization of common-path geometries has been popular for studying the cell fluctuations because of high temporal stability and low optical path difference (OPD) difference. In this paper we present a compact, efficient and highly stable setup during each kind of mechanical, optical and environmental vibrations based on Fresnel biprism interferometry. A Diode Laser module with low coherence length was used as the source. Reconstructing the intensity and phase information is possible by using fringe analysis methods. We measured OPD variations vs. time by this configuration and compared the results with an off-axis DHM setup based on Mach-Zehnder interferometer geometry. The results illustrated the great performance and nanometer accuracy of our setup in studying the morphological changes of living cells