软X射线谱学显微光束线单色器结构设计及精度测试

针对上海光源谱学显微光束线站的性能要求，对其核心部件单色器进行结构设计。阐述了单色器的扫描运动原理，论述了波长扫描机构的设计方案，具体分析平面镜和光栅的转角重复精度影响因素；描述光栅切换机构，着重分析其水平偏差、垂直偏差、滚角、摆角和投角的精度问题；采用六杆并联机构的方案完成镜箱调节机构的设计，分析其支杆的调节范围和分辨力情况。给出了单色器的结构，并且对其精度进行了测试。测试结果表明，平面镜和光栅的转角重复精度分别为0.166″和0.149″；光栅切换机构的滚角、摆角和投角的重复精度分别为0.08″、0.12″和0.05″。这说明了单色器的结构设计方案和机械精度满足技术要求。

Structure Design and Accuracy Testing of Monochromator in a Soft X-Ray Spectromicroscopic Beamline

In order to satisfy the technical requirement of soft X-ray microscopy beamline in Shanghai Synchrotron Radiation Facility (SSRF), whose key assembly monochromator is designed. Wavelength scanning movement principle of monochromator is described. Design scheme of wavelength scanning mechanism is discussed, and factors affecting the angular repeatability of plane mirror and plane grating are analyzed in detail; switching mechanism of plane grating is described, and horizontal deviation, vertical deviation, roll angle precision, yaw angle precision and pitch angle precision are analyzed in detail; six-bar parallel mechanism is used for adjusting the UHV-chamber, and adjusting range and resolution of the bar are analyzed. The entire structure of monochromator is presented, and its precision testing is performed. Results show that the angular repeatability of plane mirror and plane grating are 0.166″ and 0.149″, and roll, yaw and pitch angular repeatability of plane grating switching mechanism are 0.08″, 0.12″ and 0.05″, indicating that structure design and precision of monochromator satisfy the technical demand.