Two camera phase contrast imaging using digital correlation imaging of speckles

In this paper, we demonstrate quantitative phase contrast imaging using temporal digital speckle correlation imaging. The system consists of two identical imaging arms, where one of the arms is used as a reference and the other is used to image the phase object under study. The speckled illumination is produced by laser light scattered off a rotating diffuser. The imaging principle is based on the deflection of light in the Fourier plane of an imaging system in the presence of a phase gradient and the decorrelation this causes of a speckle pattern. In the paper, the technique is theoretically described and demonstrated both through simulations and experiments using a dried-out eye contact lens as a phase object.