磁光阱异面空间角度测量及测量不确定度评定

随着空间几何量精密测量技术在装备制造工业的制造与装配过程中应用越来越广泛，角度计量正在从平面角度向空间角度发展。针对磁光阱的异面空间角度进行测量，使用平行平晶作为标准平面引出待测面法向量，并将其空间角度有效的划分成水平投影角和竖直投影角两个平面角度进行测量，保证了空间角度的可溯源性，得到磁光阱各待测面法向量间的空间角度偏差最大值为0.286 0 mrad;然后通过蒙特卡洛法评定该方法的测量不确定度为0.095 9 mrad;最后与三坐标测量机法比对结果中偏差最大值为0.184 2 mrad,在考虑待测面平面度指标为±0.145 4 mrad时，二者的一致性良好。目前该方法已在NIM5铯原子喷泉钟物理真空子系统的研制中进行了应用，证明了该方法能够满足测量的准确度要求。

Measurement of spatial angle of different surfaces of magneto-optical trap and evaluation of measurement uncertainty

With more and more extensive application of spatial geometric precision measurement technology in the manufacturing and assembly process of equipment manufacturing industry, angle measurement is developing from plane angle to spatial angle. The spatial angle of the different planes of the magneto-optical trap is measured. A parallel flat crystal is utilized as the standard plane to draw the normal vector of the surface to be measured. The spatial angle is effectively divided into two plane angles, which are the horizontal projection angle and the vertical projection angle. The traceability of the spatial angle is guaranteed, and the maximum spatial angle deviation between the normal vectors of the measured surfaces of the magneto-optical trap is 0. 286 0 mrad. Then, the measurement uncertainty of this method is evaluated as 0. 095 9 mrad by the Monte Carlo method. Compared with the coordinate measuring machine method, the maximum deviation is 0. 184 2 mrad. When the flatness index of the surface is set to ± 0. 145 4 mrad, the consistency between the two is good. At present, this method has been applied in the development of the physical vacuum subsystem of the NIM5 cesium atomic fountain clock, which proves that the method can meet the accuracy requirements of the measurement.