Lateral shearing common-path digital holographic microscopy with iterative reconstruction

Dual-path off-axis digital holographic microscopy (DHM) has been effectively used for quantitative phase imaging applications. However, challenges are involved in its development because of complex and bulky optical systems, phase aberrations, and low temporal stability. In this work, a common-path off-axis DHM is proposed based on the lateral shearing of object-scattered wavefronts. A beam splitter, placed in the path of the object beam magnified by a microscope objective, splits the beam into two laterally sheared components to form a hologram at the detector. The optical path difference between the two beams allows reconstructing the object information in these beams in two distinct planes. As a result, the problem of image duplication, observed in other lateral-shearing-based configurations, is avoided. Furthermore, an iterative algorithm is proposed to enhance the quality of phase estimation in the focal plane by suppressing the contributions of those from out-of-focus planes. The experimental results are provided by polystyrene beads and HeLa cells. The studies on temporal stability and performance comparison with conventional dual-path DHM have also been reported.