Paper

X-ray Interferometry Using a Modulated Phase Grating: Theory and Experiments

Hidrovo, Ivan, Butler, Leslie G, Varga, Tamas, Schulz, Joachim, Kaiser, Konradin, Meyer, Hunter, Bleuel, Markus, Beckenbach, Thomas, Dey, Joyoni, Dooley, Kerry M, Ham, Kyungmin, Carr, Sydney

2024

Overview

X-ray grating interferometry allows for the simultaneous acquisition of attenuation, differential-phase contrast, and dark-field images, resulting from X-ray attenuation, refraction, and small-angle scattering, respectively. The modulated phase grating (MPG) interferometer is a recently developed grating interferometry system capable of generating a directly resolvable interference pattern using a relatively large period grating envelope function that is sampled at a pitch that allows for X-ray spatial coherence using a microfocus X-ray source or by use of a source G0 grating that follows the Lau condition. We present the theory of the MPG interferometry system for a 2-dimensional staggered grating, derived using Fourier optics, and we compare the theoretical predictions with experiments we have performed with a microfocus X-ray system at Pennington Biomedical Research Center, LSU. The theoretical and experimental fringe visibility is evaluated as a function of grating-to-detector distance. Quantitative experiments are performed with porous carbon and alumina samples, and qualitative analysis of attenuation and dark-field images of a dried anchovy are shown.

• Publisher: Cornell University Library, arXiv.org
• Subject: Attenuation / Image acquisition / Image contrast / Interferometry / Phase contrast / Qualitative analysis / Research facilities / X ray interferometry / X ray sources