Simple phase extraction in x-ray differential phase contrast imaging**Project supported by the National Natural Science Foundation of China (Grant Nos. 61101175, 61571305, and 61227802).

Abstract

A fast and simple method to extract phase-contrast images from interferograms is proposed, and its effectiveness is demonstrated through simulation and experiment. For x-ray differential phase contrast imaging, a strong attenuation signal acts as an overwhelming background intensity that obscures the weak phase signal so that no obvious phase-gradient information is detectable in the raw image. By subtracting one interferogram from another, chosen at particular intervals, the phase signal can be isolated and magnified.