LAUSR

Abstract This paper focuses on solving the diffractive phase retrieval problem of arbitrary complex objects by modulating the object phase. Unlike classical diffraction interferometry such as point-diffraction and phase-shifting interferometry, this method does not require precise location, size, information on the phase shifting area, or direct reference waves. By considering regional division and small area phase shift on the object plane, one can obtain relatively accurate object reconstruction with few algebraic calculations. To simplify the scheme, a structured phase grate is designed to split the diffraction beam into four parts so that quantitative phase imaging (QPI) is achieved simultaneously with a combined phase mask. Simulations and experiments demonstrate that this method is applicable to real-time QPI for coherent diffraction imaging (CDI).