Angular sensitivity and spatial resolution in edge illumination X-ray phase-contrast imaging

Edge illumination (EI) is an X-ray phase-contrast imaging (XPCi) technique which bears high potential for applications in several fields, thanks to its simple experimental setup and to its applicability with conventional X-ray sources. In this context, the estimation of the phase sensitivity and spatial resolution achievable with EI is of particular importance, as it will enable assessing and quantifying the full potential of the technique. We present in this article a simple theoretical model that allows the analysis of these two quantities and of their dependence upon the different acquisition parameters. We believe that the obtained results will prove very useful for the design and optimization of future setups. Besides, we demonstrate experimentally that the simplicity of the EI setup does not come at the expense of the sensitivity; on the contrary, EI allows achieving very high angular resolutions.