X-ray phase-contrast imaging is a promising method for medical imaging and non-destructive testing. Information about the attenuation, small-angle scattering and phase-shifting properties of an object can be gained simultaneously in three image modalities using a Talbot-Lau interferometer. This is a highly sensitive approach for retrieving this information. Nevertheless, until now, Talbot-Lau interferometry has been a time-consuming process due to image acquisition by phase-stepping procedures. Thus, methods to accelerate the image acquisition process in Talbot-Lau interferometry would be desirable. This is especially important for medical applications to avoid motion artifacts. In this work, the Talbot-Lau interferometry is combined with the moiré imaging approach. Firstly, the reconstruction algorithm of moiré imaging is improved compared to the standard reconstruction methods in moiré imaging that have been published until now. Thus, blurring artifacts resulting from the reconstruction in the frequency domain can be reduced. Secondly, the improved reconstruction algorithm allows for reducing artifacts in the reconstructed images resulting from inhomogeneities of the moiré pattern in large fields of view. Hence, the feasibility of differential phase-contrast imaging with regard to the integration into workflows in medical imaging and non-destructive testing is improved considerably. New fields of applications can be gained due to the accelerated imaging process-for example, live imaging in medical applications.

X-ray grating-based phase-contrast imaging is a very promising imaging technique for medical imaging and non-destructive testing. Simultaneously to the attenuation properties additional information about the phase-shift and the scattering properties of an object can be gained. Nevertheless, to obtain this information multiple shots per image have to be taken in the so-called phase-stepping process. Thus, it often is a time consuming imaging procedure. In contrast, Moiré imaging with a Talbot-Lau interferometer is a very fast single-shot imaging method. To obtain the Moiré pattern which encodes the object information the interferometer has to be slightly detuned. This leads to a loss in visibility and therefore to a loss in image quality compared to the more time consuming phase-stepping method. Thus, it is important for the Moiré imaging method to evaluate the mechanisms of visibility loss. In this publication we present measurements and simulations investigating the visibility loss due to detuning the Talbot-Lau interferometer. Thus, a deeper understanding of Moiré imaging can be gained.

Talbot-Lau x-ray imaging provides additionally to the conventional attenuation image, two further images: the differential phase-contrast image which is especially sensitive to differences in refractive properties and the dark-field image which is showing the x-ray scattering properties of the object. Thus, in the dark-field image sub-pixeled object information can be observed. As it has been shown in recent studies, this is of special interest for lung imaging. Changes in the alveoli structure, which are in the size of one detector pixel, can be seen in the dark-field images. A fast acquisition process is crucial to avoid motion artifacts due to heartbeat and breathing of the patient. Using moiré imaging the images can be acquired with a single-shot exposure. Nevertheless, the spatial resolution is reduced compared to the phase-stepping acquisition. We evaluate the results of both imaging techniques towards their feasibility in clinical routine. Furthermore, we analyse the influence of artificial linear object movement on the image quality, in order to simulate the heartbeat of a patient.

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