X-ray absorption, phase and dark-field tomography through a beam tracking approach.

Sci Rep

Department of Medical Physics and Biomedical Engineering, University College London, Malet Place, Gower Street, WC1E 6BT London, United Kingdom.

Published: November 2015

We present a development of the beam-tracking approach that allows its implementation in computed tomography. One absorbing mask placed before the sample and a high resolution detector are used to track variations in the beam intensity distribution caused by the sample. Absorption, refraction, and dark-field are retrieved through a multi-Gaussian interpolation of the beam. Standard filtered back projection is used to reconstruct three dimensional maps of the real and imaginary part of the refractive index, and of the dark-field signal. While the method is here demonstrated using synchrotron radiation, its low coherence requirements suggest a possible implementation with laboratory sources.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4635357PMC
http://dx.doi.org/10.1038/srep16318DOI Listing

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