Dual phase grating interferometer for x-ray phase contrast imaging

TLDR: In this paper, the authors proposed a system based exclusively on X-ray phase shifting components, without the use of an absorption grating, or a mask or a high-resolution detector.

Abstract: Since the very first experiments with phase-contrast imaging at synchrotrons, X-ray scientists were quite excited by the potential of this novel approach, as the "holy-grail" of boosting the contrast of soft and radiation sensitive materials under dose-control seemed to be finally at reach. The features of gratings-based interferometry (GI) are well suited for transferring this exciting technology from the exclusive synchrotron's community to a much wider basin of potential users. Particularly for medical applications, the relation between image contrast and dose has triggered tremendous efforts in the development of novel imaging devices. Such systems essentially operate near to the photon-starvation limit to cope with the fundamental dilemma of providing sufficient diagnostic sensitivity and sensibility at an acceptable, as low as reasonably achievable (ALARA) risk for the patient. If a new imaging modality were to be implemented in a clinical environment, it is needless to say that it has to be compliant with the very strict regulatory directives. The present invention proposes a system based exclusively on X-ray phase shifting components, i.e. without the use of an absorption grating, or a mask or a high-resolution detector. The novel approach is applicable at all imaging relevant energies and can be easily scalable to large field of views. The invention solves in one shot most the major limitations so far which were preventing a broad dissemination of phase contrast X-ray imaging on conventional sources.