Complementary coded apertures for 4-dimensional x-ray coherent scatter imaging
Complementary coded apertures for 4-dimensional x-ray coherent scatter imaging
复制标题
DOI：
10.1364/oe.22.022925
复制
发表时间：
2014-09-22
期刊：
影响因子：
3.8
通讯作者：
Brady, David
中科院分区：
文献类型：
--
作者：
Pang, Shuo;Hassan, Mehadi;Brady, David
由于材料特有的相干散射特征，X射线散射在非破坏性材料表征中起着关键作用。在目前的能量色散相干散射成像系统中，包括选择体积层析成像和相干散射计算机层析成像，每个目标体素都是在单个散射角测量的，这存在采集时间慢的问题。编码孔径在X射线散射成像系统中的应用提高了光子收集效率，使其在实时体积成像和材料识别方面具有广阔的应用前景。在本文中，我们提出了一种使用一对互补编码孔径的体积X射线散射成像系统：探测器侧的编码孔径在能量敏感的探测器阵列上引入多路测量；互补的源侧编码孔径选择性地照亮物体，以消除由于4D成像的并行化增加而产生的模糊。该系统在3D中的每个体素处产生1D相干散射形状因子。我们用该系统演示了层析成像和物质识别，并获得了类似于1厘米的空间分辨率和归一化动量传递分辨率Delta Q/Q为0.2。(C)2014年美国光学学会
X-ray scattering has played a key role in non-destructive materials characterization due to the material-specific coherent scattering signatures. In the current energy dispersive coherent scatter imaging systems, including selected volume tomography and coherent scatter computed tomography, each object voxel is measured at a single scatter angle, which suffers from slow acquisition time. The employment of coded apertures in x-ray scatter imaging systems improves the photon collection efficiency, making it promising for real time volumetric imaging and material identification. In this paper, we propose a volumetric x-ray scatter imaging system using a pair of complementary coded apertures: a coded aperture on the detector side introduces multiplexed measurement on an energy-sensitive detector array; a complementary source-side coded aperture selectively illuminates the object to decouple the ambiguity due to the increased parallelization for 4D imaging. The system yields the 1D coherent scattering form factor at each voxel in 3D. We demonstrate tomographic imaging and material identification with the system and achieve a spatial resolution similar to 1 cm and a normalized momentum transfer resolution, Delta q/q, of 0.2. (C) 2014 Optical Society of America