高精度平面光栅尺测量系统的模型设计与安装误差分析

High-Precision Encoder Measuring System Model Design and Installation Error Analysis

本文分析了高精度平面光栅尺的测量原理,推导了工件台坐标系的位置关系,利用读头光束与光栅平面的几何关系,建立光斑位移与工件台位置的关系,实现了将平面光栅尺测出的莫尔条纹数转化为工件台的位置信息。平面光栅尺测量系统在安装过程中,读头和光栅均存在沿X方向、Y方向上的平移偏差和绕X轴、Y轴和Z轴的旋转误差,本文利用组合分析的方法,推导出模型约束出安装误差的最大范围。通过仿真分析可知,模型设计精度要求为1×1010m时,读头平移误差范围在-1×10-3m～1×10-3m、读头旋转误差的范围-8×10-4rad～8×10-4rad、光栅旋转误差的范围为-1×10-4rad～1×10-4rad下,可以满足相应的设计指标,为实际的工程应用提供有效的理论依据。

In this paper,we analyze the measuring principle of a high-precision encoder,the location of the stage coordinate system,and the relationship between the reading ofthe beam and the geometry of the grating plane,and the relationship to the position ofthe encoder,it is the location of the transfer of the Mohr to the stage.In the process of the installation of the encoder measuring system,the head and the grating are the same as the rotation of the X-axis,the Y-axis,and the axis of the X-axis,and the axisof the X-axis,and the axis of the X-axis and the axis of the axis,and the way that this is done,is to use the method of combinational analysis,and use the derived modelto restrain the maximum range of the set error.According to the simulation analysis,when the model design accuracy is required to be 0.1nm,the translation error range of the reader head is from-1mm to+1mm,the rotation error range of the reader head is from-0.8urad to+0.8urad,and the rotation error range of the grating is from-0.1mm to+0.1mm,which can meet the corresponding design index and provide effective theoretical basis for practical engineering applications.