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arXiv · 1412.6824

Spherical-Wave Far-Field Interferometer for Hard X-Ray Phase Contrast Imaging

Houxun Miao·Andrew A. Gomella·Katherine J. Harmon·Eric E. Bennett·Nicholas Chedid·Alireza Panna·Priya Bhandarkar·Han Wen
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Abstract

Low dose, high contrast x-ray imaging is of general interest in medical diagnostic applications. X-ray Mach-Zehnder interferometers using collimated synchrotron beams demonstrate the highest levels of phase contrast under a given exposure dose. However, common x-ray sources emit divergent cone beams. Here, we developed a spherical-wave inline Mach-Zehnder interferometer for phase contrast imaging over an extended area with a broadband and divergent source. The first tabletop system was tested in imaging experiments of a mammographic accreditation phantom and various biological specimens. The noise level of the phase contrast images at a clinical radiation dose corresponded to a 6 nano radian bending of the x-ray wavefront. Un-resolved structures with conventional radiography and near-field interferometer techniques became visible at a fraction of the radiation dose.

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Houxun Miao, Andrew A. Gomella, Katherine J. Harmon, Eric E. Bennett, Nicholas Chedid, Alireza Panna, Priya Bhandarkar, Han Wen. 2014-12-21. Spherical-Wave Far-Field Interferometer for Hard X-Ray Phase Contrast Imaging. https://arxiv.org/abs/1412.6824

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