标准硅球直径精密测量中光束对准误差分析

Error analysis of beam alignment for measuring the diameter of a silicon sphere with high precision

单晶硅球直径的准确测量是阿伏加德罗常数测量中一项重要内容,并决定着最终的测量不确定度。针对高精度硅球直径测量系统双光路的特点,在不考虑图像圆心提取误差的情况下,运用几何关系推导,分别就平行光束垂直于标准板和以一定角度斜入射标准板条件下引入的测量误差进行了研究,分析了直径测量误差随光束对准误差的变化。结果表明在保证一定的光束对准精度条件下,其对测量系统最终的精度影响是可以忽略的。

Accurate measurement for the diameter of single crystal silicon sphere is one of the most important parts for measuring Avogadro constant, and also decides the final uncertainty of measurement. According to the characteristic of the double optical path of the system, formulas are deduced using geometrical relationship, without considering errors in the image processing for extracting the interference circular center. The measuring errors of the diameter are discussed respectively when the incident beam is n...