Applying the Fokker-Planck equation to grating-based x-ray phase and dark-field imaging.

ABSTRACT: X-ray imaging has conventionally relied upon attenuation to provide contrast. In recent years, two complementary modalities have been added; (a) phase contrast, which can capture low-density samples that are difficult to see using attenuation, and (b) dark-field x-ray imaging, which reveals the presence of sub-pixel sample structures. These three modalities can be accessed using a crystal analyser, a grating interferometer or by looking at a directly-resolved grid, grating or speckle pattern. Grating and grid-based methods extract a differential phase signal by measuring how far a feature in the illumination has been shifted transversely due to the presence of a sample. The dark-field signal is extracted by measuring how the visibility of the structured illumination is decreased, typically

SUBMITTER: Morgan KS 

PROVIDER: S-EPMC6877582 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature