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arXiv · 1009.1380

Compressive Phase Contrast Tomography

F. R. N. C. Maia·A. MacDowell·S. Marchesini·H. A. Padmore·D. Y. Parkinson·J. Pien·A. Schirotzek·C. Yang
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Abstract

When x-rays penetrate soft matter, their phase changes more rapidly than their amplitude. In- terference effects visible with high brightness sources creates higher contrast, edge enhanced images. When the object is piecewise smooth (made of big blocks of a few components), such higher con- trast datasets have a sparse solution. We apply basis pursuit solvers to improve SNR, remove ring artifacts, reduce the number of views and radiation dose from phase contrast datasets collected at the Hard X-Ray Micro Tomography Beamline at the Advanced Light Source. We report a GPU code for the most computationally intensive task, the gridding and inverse gridding algorithm (non uniform sampled Fourier transform).

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F. R. N. C. Maia, A. MacDowell, S. Marchesini, H. A. Padmore, D. Y. Parkinson, J. Pien, A. Schirotzek, C. Yang. 2010-09-07. Compressive Phase Contrast Tomography. https://doi.org/10.1117/12.861946

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