Conventional computed tomography (CT) only reconstructs the attenuation map within a sample. X-ray coherent scattering computed tomography (CSCT), which probes the angular-dependent scattering profiles of a 3D object, achieves high-contrast and specificity among materials or tissues with similar attenuation cross-section. Due to the weak coherent scattering cross-section, CSCT using a pencil-beam either requires a brilliant source, such as synchrotron, or tens of hours in image acquisition using a traditional X-ray tube. Fan-beam CSCT using table-top source has been proposed to parallelize the acquisition of each projection, but the use of collimators on the detector plane limits the collection efficiency. Moreover, conventional CSCT systems cannot further parallelize the image acquisition among layers by switching to cone-beam illumination, because the scattering signal from different layers will overlap on the detector. Here we propose a fast, high-efficiency multiplexing scheme using structured cone-beam illumination to image a 3D sample. Our system improves the source utilization compared to pencil-beam CSCT, yet does not require detector collimator to localize and resolve the scattering profile of each point. We have reconstructed the coherent scattering profile within a volumetric object, and demonstrated the material classification of the 3D sample. Compared to previous systems, our method reduces the imaging time by one order of magnitude. We believe our multiplexed CSCT scheme could become the next generation X-ray coherent scattering tomography system.
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