便携式微束X射线荧光谱仪的研发

研制了便携式微束X射线荧光谱仪，并对其硬件、软件和性能等特征进行了分析。该谱仪应用激光位移传感器实时检测样品测量点到透镜出端之间的距离并自动调节该距离的方法，来解决考古样品表面不平整或弧度而造成的照射样品X射线束斑变化的问题，从而保证X射线照射光斑大小不变。为验证谱仪的可靠性，采用该谱仪测量了表面高度差接近5 mm的古陶瓷样品微区的釉彩层元素的分布。分析结果表明，激光位移传感器能有效减少由于样品表面不平整或弧度带来的测量误差。此外，使用本谱仪分析了5角硬币表面4 mm×4 mm的区域，经过数据处理后得到Cu、Sn等元素的分布及其合金相的分布，表明该谱仪不仅可进行微区能量色散X射线荧光分析（μ-EDXRF），同时还可进行微区能量色散X射线衍射分析（μ-EDXRD）。

Development of Portable Micro-X-ray Fluorescence Spectrometer

The portable micro-X-ray fluorescence spectrometer was developed and its hardware, software and performances were analyzed in this paper. In this spectrometer, the distance between the irradiation spot of sample and exit of polycapillary X-ray optics was automatically controlled by laser displacement sensor (LDS). By this way, the sizes of focused X-ray spot keep constants in order to decrease the errors caused by irregular or curving surface of archaeological object. In order to test the feasibilities of this spectrometer, the elemental mappings on the irregular colored glaze of a piece of ancient porcelain whose height difference is nearly 5 mm were scanned by portable micro-X-ray fluorescence spectrometer. The experimental results show that LDS can effectively reduce measurement errors caused by irregularity or curvature of sample surface. In the same time, an area with a size of 4 mm×4 mm on the RMB 5 Jiao coin’s surface was measured by the spectrometer, and the distributions of Cu, Sn and their alloys’ crystal phases were got after data processing. It indicates that this spectrometer not only can do micro energy dispersion X-ray fluorescence analysis (μ-EDXRF), but also can do micro energy dispersion X-ray diffraction analysis (μ-EDXRD).