Coded aperture ptychography

The Coded Ptychography (CP) achieves robust phase reconstruction by combining coded layers and overlapping scanning, however the requirement for a high scan overlap rate leads to a conflict between measurement precision and efficiency. This research suggests Coded Aperture Ptychography (CAP) as a solution to this issue. The amplitude modulation function of the spatial light modulator is employed to encode the detecting light's aperture, guaranteeing a consistent corresponding coding layer for every scan and offering ample phase diversity to enable high-precision phase recovery. In addition, to reduce the measurement complexity, a phase retrieve algorithm was proposed to reconstruct the object, incident beam, and coding layer all at once, and the absorption and amplitude constraints of the coding layer aperture were introduced to improve measurement efficiency and accuracy. We demonstrate in simulated studies that when the overlap rate is decreased to 0.2, the measurement accuracy of the CAP technique can be comparable to that of the CP method when the overlap rate is 0.8, and the number of algorithm iterations is lowered to a seventh.