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arXiv · 1108.1414

Differential Phase-contrast Interior Tomography

Wenxiang Cong·Ge Wang
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Abstract

Differential phase contrast interior tomography allows for reconstruction of a refractive index distribution over a region of interest (ROI) for visualization and analysis of internal structures inside a large biological specimen. In this imaging mode, x-ray beams target the ROI with a narrow beam aperture, offering more imaging flexibility at less ionizing radiation. Inspired by recently developed compressive sensing theory, in numerical analysis framework, we prove that exact interior reconstruction can be achieved on an ROI via the total variation minimization from truncated differential projection data through the ROI, assuming a piecewise constant distribution of the refractive index in the ROI. Then, we develop an iterative algorithm for the interior reconstruction and perform numerical simulation experiments to demonstrate the feasibility of our proposed approach.

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Wenxiang Cong, Ge Wang. 2011-08-05. Differential Phase-contrast Interior Tomography. https://doi.org/10.1088/0031-9155%2F57%2F10%2F2905

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