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arXiv · 2407.20304

X-ray nano-holotomography reconstruction with simultaneous probe retrieval

Viktor Nikitin·Marcus Carlsson·Doga Gursoy·Rajmund Mokso·Peter Cloetens
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Abstract

In conventional tomographic reconstruction, the pre-processing step includes flat-field correction, where each sample projection on the detector is divided by a reference image taken without the sample. When using coherent X-rays as probe, this approach overlooks the phase component of the illumination field (probe), leading to artifacts in phase-retrieved projection images, which are then propagated to the reconstructed 3D sample representation. The problem intensifies in nano-holotomography with focusing optics, that due to various imperfections create high-frequency components in the probe function. Here, we present a new iterative reconstruction scheme for holotomography, simultaneously retrieving the complex-valued probe function. Implemented on GPUs, this algorithm results in 3D reconstruction resolving twice thinner layers in a 3D ALD standard sample measured using nano-holotomography.

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Viktor Nikitin, Marcus Carlsson, Doga Gursoy, Rajmund Mokso, Peter Cloetens. 2024-07-29. X-ray nano-holotomography reconstruction with simultaneous probe retrieval. https://arxiv.org/abs/2407.20304

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