Real time 3D coherent X-ray diffraction imaging

Fangzhou Ai; Oleg Shpyrko; Vitaliy Lomakin

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arXiv · 2402.05283

Real time 3D coherent X-ray diffraction imaging

Fangzhou Ai·Oleg Shpyrko·Vitaliy Lomakin

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Abstract

Coherent X-ray Diffraction Imaging (CXDI) technique offers unique insights into the nanoscale world, enabling the reconstruction of 3D structures with a nanoscale resolution achieved through computational phase reconstruction from measured scattered intensity maps. Computational demands of 3D CXDI, however, limit its real-time application in experimental settings. This work presents a carousel phase retrieval algorithm (CPRA) that enables the real-time, high-resolution reconstruction of computationally complex 3D objects. CPRA is based on representing the 3D reconstruction problem as a set of 2D reconstructions of projected images corresponding to different experimentally collected angles via the Fourier slice theorem. Consistency between the 2D reconstructed images is based on an iterative procedure, in which each 2D reconstruction accounts for the adjacent 2D reconstructed images in a periodic (carousel) manner. Demonstrations on complex systems, including a lithium-rich layered oxide particle and a Staphylococcus aureus biological cell, demonstrate that CPRA significantly enhances the reconstruction quality and enables the reconstruction process to be completed in real time during experiment.

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Fangzhou Ai, Oleg Shpyrko, Vitaliy Lomakin. 2024-03-23. Real time 3D coherent X-ray diffraction imaging. https://arxiv.org/abs/2402.05283

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