Blind Ptychography by Douglas-Rachford Splitting

Blind ptychography is the scanning version of coherent diffractive imaging which seeks to recover both the object and the probe simultaneously. Based on alternating minimization by Douglas-Rachford splitting, AMDRS is a blind ptychographic algorithm informed by the uniqueness theory, the Poisson noise model and the stability analysis. Enhanced by the initialization method and the use of a randomly phased mask, AMDRS converges globally and geometrically. Further, the technique of bright-field boundary condition is introduced to remove the linear phase ambiguity and accelerate convergence, and the technique of adding salt noise is used to improve the quality of reconstruction of objects exhibiting extensive area of dark pixels.