Optimization of propagation-based phase-contrast imaging at a laboratory setup

Abstract

Single distance X-ray propagation-based phase-contrast imaging is considered as a simple method compared to those requiring additional precise instruments and sophisticated algorithms to retrieve phase images. It requires, however, a modicum of conditions within the setup which include partial coherence and small pixel size at the sample position. While these conditions are usually satisfied at synchrotron light sources, they are not always satisfied within laboratory setups. In fact, these setups are limited by the size of the polychromatic source that directly influences the partial coherence of the beam, the propagation distance and the photon flux. A prior knowledge of the sample refractive index, namely the ratio of delta (δ) and beta (β) values, are also essential for the phase retrieval but this method is powerful in the presence of noise compared to absorption-based imaging. An investigation of the feasibility and the efficient applicability of this method in a commercially available X-ray microscope is conducted in this work.