基于波带片纳米聚焦装置的快速扫描X射线荧光成像实验系统

Fast Scanning X-ray Fluorescence Imaging Experimental System Based on Zone Plate Nano-focusing Device

在上海光源硬X射线微聚焦光束线站BL15U1,为提高波带片纳米聚焦装置的X射线荧光成像实验效率,设计实现了一种快速扫描荧光成像实验装置。该装置包括运动控制系统、样品荧光探测系统和实验数据同步获取系统。运动控制系统设计了闭环反馈控制、样品台电机运动控制和扫描轨迹,实现了快速扫描过程中样品的准确定位。样品荧光探测系统和实验数据同步获取系统实现了硬件同步触发计数器获取荧光计数,保证了荧光成像的准确性。实验结果表明,运动控制系统三角波形跟踪误差小于20 nm,满足光斑在样品处的重复定位精度小于光斑尺寸1/10的要求。用该系统获取了标准铜网的元素分布图像,图像获取时间是“走停”扫描模式的1/5,验证了实验系统的可行性和高效性。

In the Shanghai Synchrotron Radiation Facility hard X-ray micro-focusing beamline station BL15U1,in order to improve the X-ray fluorescence imaging experiment efficiency of the zone plate nano-focusing device,a fast scanning fluorescence imaging experimental device was designed and implemented.The device includes a motion control system,a sample fluorescence detection system and an experimental data synchronization acquisition system.The motion control system was designed with closed-loop feedback control,sample stage motor motion control and scanning trajectory to achieve accurate positioning of samples during fast scanning.The sample fluorescence detection and experimental data synchronization acquisition systems were designed to realize the hardware synchronous trigger counter to obtain the fluorescence counts,which ensures the accuracy of fluorescence imaging.The experimental results show that the triangular waveform tracking error of the motion control system is less than 20 nm,which satisfies the requirement that the repeatability of the spot at the sample is less than 1/10 of the spot size.The element distribution image of the standard copper mesh is obtained by the system,and the image acquisition time is 1/5 of that in the“step-by-step”scanning mode,which confirms the feasibility and efficiency of the experimental system.