Parameter optimization for a grating-based phase contrast X-ray system

Differential Phase Contrast Imaging (DPCI) has the potential to vastly increase soft tissue contrast. DPCI requires spatial and temporal coherence as generated by a synchrotron or a micro-focus X-ray source; however, recent research demonstrates DPCI can be implemented using a conventional X-ray source with three transmission ratings (Pfeiffer et al., Nature 2006). This paper describes the optimization of the essential system parameters (system size, delivered dose, spatial resolution) of this implementation from a theoretical perspective. The optimization of these parameters is an essential step in practical application of DPCI. We conclude that the minimum size of the system is approximately 700 mm, the minimum resolution is 100 um, and the dose is 1/1000 that of conventional absorption CT.