由于大型衍射光栅刻划机刻划系统的双拉杆结构不能使其满足精度指标要求,本文设计了一套单拉杆结构.讨论了石英导轨分度方向弯曲误差产生的原因及其减小该误差的方法,分析和比较了两种拉杆结构的鞍型滑块的受力情况.基于材料力学弯曲变形理论,建立了石英导轨分度方向弯曲误差模型.在该模型的基础上仿真了双、单拉杆结构下刻划系统的石英导轨在分度方向上的弯曲变形误差.最后,使用双频激光干涉仪对石英导轨上的两个特征测量点进行了测量.测量结果显示:改进后的拉杆结构使得石英导轨在两特征测量点处的位移误差由50.36 nm降低到小于10 nm,满足大型衍射光栅刻划机刻划系统在分度方向上5~10 nm的精度指标要求.

As the double-rod structure in ruling system of a large diffraction grating ruling machine can not meet its accuracy requirement,this paper designs a single-rod structure to substitute it.The reasons of bending error of indexing direction of quarts guide rail in the grating ruling machine were discussed and the method to reduce the error was analyzed.Meanwhile the rod structure and the stress on a saddle slider were analyzed.Then,based on the theory of bending deformation of material mechanics,the model of bending error in indexing direction of quartz guide rail was established.On the basis of this model,the bending errors of quartz guide rails on the double-rod structure and the single-rod structure were simulated.Finally,a frequency laser interferometer was used to measure the two feature points on quartz guide rail.Experimental results indicate that the bendings at the measuring points of quartz guide rail are reduced from 50.36 nm to less than 10 nm by using the single-rod struture.It concludes that the single-rod structure basically meets the requirement of large diffraction grating ruling engine for the measuring precision of 5—10 nm.