Xiong Genchao, Jia Wenbao, Shan Qing, Zhang Xinlei, Tang Xinru, Li Jun
College of Materials Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China.
Rev Sci Instrum. 2020 Dec 1;91(12):123701. doi: 10.1063/5.0024461.
This work describes a full field x-ray fluorescence element distribution imaging system with a combined collimating lens (CCL), which is more suitable for a higher x-ray energy range (12 keV-30 keV). The system consists of an optical-use charge-coupled device (CCD) camera coupled to a combined collimating lens (CCL), which includes pinhole collimator and x-ray window, x-ray tube, and sample room. The continuously variable magnification of 0.5-2 is achieved under a compact structure. The x-ray spectrum and two-dimensional element distribution mapping of the irradiated sample are obtained by processing a series of images acquired by using the CCD camera in a single photon counting mode. The energy resolution is 275 eV at the reference energy of 14.957 keV (yttrium Kα, Z = 39). The limit of detection is 46.41 ppm by measuring yttrium standard solution. The spatial resolution is 135 μm when using a 100 μm pinhole at the magnification of 1. Samples made by metal foils and mineral pigments are tested, and the results proved that the system was reliable when detecting elements of a high atomic number.
这项工作描述了一种带有组合准直透镜（CCL）的全场X射线荧光元素分布成像系统，该系统更适用于较高的X射线能量范围（12 keV - 30 keV）。该系统由一个与组合准直透镜（CCL）耦合的光学用电荷耦合器件（CCD）相机组成，组合准直透镜包括针孔准直器和X射线窗口、X射线管以及样品室。在紧凑的结构下实现了0.5 - 2的连续可变放大倍率。通过处理以单光子计数模式使用CCD相机获取的一系列图像，得到被辐照样品的X射线光谱和二维元素分布图。在14.957 keV（钇Kα，Z = 39）的参考能量下，能量分辨率为275 eV。通过测量钇标准溶液，检测限为46.41 ppm。当在1倍放大倍率下使用100μm针孔时，空间分辨率为135μm。对由金属箔和矿物颜料制成的样品进行了测试，结果证明该系统在检测高原子序数元素时是可靠的。
