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X-ray phase tomography of a moving object

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We propose an algorithm for tomographic reconstruction of the refractive index map of an object translated across a fan-shaped X-ray beam. We adopt a forward image model valid under the non-paraxial condition, and use a unique mapping of the acquired projection images to reduce the computational cost. Even though the imaging setup affords only a limited angular coverage, our algorithm provides accurate refractive index values by employing the positivity and piecewise-smoothness constraints. (C) 2013 Optical Society of America
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