分类: 物理学 >> 电磁学、光学、声学、传热、经典力学和流体动力学 提交时间: 2023-09-06
摘要: Theaim of this researchis to reconstruct the 3D X-ray refractive index gradient mapsbythe proposed vector Radon transform and its inverse, assuming that the small-angle deviation condition is met. Theoretical analysesshowthat the X-ray beam can be modeled as a streamline with continuous change of direction in a rowwhen measured in one grating period, which allowsthe extraction of the refraction angle signals.Experimental results show thatall the 2D refraction signals of different directions can be acquired by a standard circular scanning procedure, which is typically used in the X-ray differential phase-contrast computed tomography. Furthermore, the 3D refractive index gradient maps that contain the directional density changes, can also be accurately reconstructed.