纳弧度分辨的X射线单色器布拉格转轴研究  

Research on a Bragg Rotation Mechanism of X-ray Monochromators with a Nanoradian Resolution

作　　者：刘孟廷 类维政 宋丽 夏思宇 凤良杰[4] 董晓浩(指导) 王劼[1,2] LIU Mengting;LEI Weizheng;SONG Li;XIA Siyu;FENG Liangjie;DONG Xiaohao;WANG Jie(Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China;Shanghai Advanced Research Institute,Chinese Academy of Sciences,Shanghai 201204,China;University of Chinese Academy of Sciences,Beijing 100049,China;Xi'an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi'an 710119,China)

机构地区：[1]中国科学院上海应用物理研究所,上海201800 [2]中国科学院上海高等研究院,上海201204 [3]中国科学院大学,北京100049 [4]中国科学院西安光学精密机械研究所,西安710119

出　　处：《光子学报》2022年第5期237-246,共10页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.11935020,U1832172);中科院“BR计划”人才项目(2018);上海市市级科技重大专项(No.2017SHZDZX02)。

摘　　要：为了满足同步辐射衍射极限环、X射线自由电子激光装置等新一代光源光束线中对高稳定机械运动机构在大角度范围内的纳弧度角度分辨需求,研制了一种X射线单色器晶体布拉格角调节装置。此装置将优化改良的偏置式曲柄滑块机构与柔性铰链结合。本文分析了平移-角度正弦的运动学关系,建立了运动机构的优化模型,并利用高精度非接触激光干涉测量方法进行了精确的角位移监测。结果表明:该装置传动性能、角度分辨率和角度稳定性基本符合模型的分析结果,且在线性传动关系范围内,角度分辨率优于31.2 nrad;在800 s时间内角度稳定性优于16 nrad。该机构的设计对晶体单色器的使用具有极大的便利性,并为实现十纳弧度量级角度稳定性关键技术攻关奠定了基础。The new-generation X-ray light sources based on accelerators,Diffraction-limited Storage Rings(DLSRs),and X-ray Free-electron Lasers(XFELs),have excellent properties such as high brightness,high coherence,and high collimation,which has enhanced important opportunities for scientific research and technological development.In the meantime,that brings a lot of challenges on the photon beam manipulation as well,the performance demand of optical components have been greatly improved,and at the same time,the attitude adjustment accuracy of optical components has generally entered the“micro/nano”range,such as the resolution of linear motion and angular rotation of optical components are supposed to reach a level of sub-nanometre and nanoradian.In the construction of the beamline,the monochromator is one of the core equipment to guarantee the optical performance of the beamline.In order to meet requirements of high stability and motion precision of beamline optics,for crystal monochromators in the new-generation light sources,a mechanism with a nano-radian angular resolution,driven by piezoelectric nano-displacement stages was developed.An optimized slider-crank mechanism is adopted for a large angle range of tens of degrees,so that a broader energy range can be covered with relatively big Bragg diffraction angles.This paper presents the main design parameters of the offset slider-crank mechanism for crystal monochromators according to the demand of energy range,the energy resolution and the required linear transmission ratio of X-ray crystal monochromator.By establishing a geometrical model of the slider-crank mechanism,it turns out that the transmission ratio between the linear displacement and the Sine of the Bragg angle depends solely on the crank rod length.Therefore,the length of crank rod can be determined according to the transmission ratio.At the same time,an optimized model of the offset slider-crank mechanism parameters is established in this paper,and the length of the connecting rod was determined accord

关 键 词：偏置式曲柄滑块机构 纳弧度分辨 稳定性 角度测量 线性关系 

分 类 号：O434[机械工程—光学工程]