Envelope modulated x-ray grating interferometry

X-ray dark-field and phase contrast imaging using grating interferometry (GI) have demonstrated great potential for medical and industrial applications. GI relies on the fabrication of high-quality absorption gratings, which has revealed to be quite challenging. This paper proposes an interferometer for dark-field and differential phase contrast imaging using a single phase-shifting element. This proposal simplifies the setup without penalizing the image quality. The proposed interferometer consists of a single dual-period phase grating having two distinct periods, which generates intensity modulation with a period large enough to be resolved directly by the detector. This makes the proposed GI system easily adaptable as there are no stringent alignment requirements. We show the utility of this method for a possible diagnostic task by imaging smoked murine lung samples. The simplicity of the proposed setup compared to a conventional Talbot(-Lau) interferometer suggests that it could be easily and widely used for a variety of applications.