Phase retrieval based on pupil scanning modulation.

The pupil scanning modulation is a maneuverable method for retrieving the phase of the complex-valued object. It is based on changing the extent of the illumination function using an adaptive aperture. The apertures are fixed on the same border or point of intersection that ensures the location of the aperture. We sequentially increase the size of the aperture and guarantee the necessary overlap between adjacent object fields. An improved algorithm including the adaptive raised-power estimation constraint and gradient-descent step is proposed to accelerate convergence and avoid stagnation during iterations. Both the simulation and experiment have been conducted to verify the feasibility of this method. [ABSTRACT FROM AUTHOR]