Design and development of a prism–mirror module for single-shot phase retrieval of a microlens

In various phase retrieval methods, the phase is retrieved by measuring the intensity of propagating light waves at multiple planes by moving the detector in the longitudinal direction and then solving the phase retrieval problem by deterministic or iterative methods. In this article, we present the design and development of a prism–mirror based optical module to capture simultaneously two defocused intensity images at different planes in single-shot. The proposed method has been applied for the transmitted wavefront measurement of the microlens and its phase retrieval using the transport of intensity equation. The results obtained by this method have been compared with interferometry-based measurements.