五维自由度衍射光栅精密测量系统（英文）

为了在保证结构简单的前提下,实现衍射光栅精密测量系统的大量程、高精度、多维度测量,设计了能够同时测量位移和角度的五维自由度衍射光栅精密测量系统。基于利特罗对称式光路结构,采用高刻线密度的一维衍射光栅以及外差干涉原理实现了沿光栅矢量方向和光栅法线方向的二维位移测量;通过引入高精度的位置灵敏探测器,结合±1级衍射光与光栅之间的角度变化关系实现了对光栅俯仰、偏摆和滚转三个维度的角度误差测量。实验结果表明:该衍射光栅精密测量系统能够实现分辨力优于4 nm的二维位移测量以及分辨力优于1″的三维角度测量,其位移测量范围只受限于光栅的尺寸,量程大大增加。该衍射光栅精密测量系统在精密测量领域有重要意义。

Grating-based precision measurement system for five-dimensional measurement

To realize large range,high precision and multi-dimensional measurement with a relatively simple structure,a grating-based precise measurement system is designed for five-dimensional measurement including simultaneous measurement of displacement and angle.Based on symmetrical Littrow structure and heterodyne interference principle,two-dimensional displacement measurement along grating's vector direction and normal direction is realized by using one-dimensional diffraction grating with high groove density.What's more,the angle errors of pitch,yaw and roll of grating are measured by using high precision position sensitive detectors considering the angular variation between±1 st order diffraction light and grating.Experimental results indicate that the proposed grating-based precision measurement system can achieve high precision and large range displacement measurement with resolution better than 4 nm.It can also realize high precision angle error measurement with resolution better than 1″.Moreover,because the displacement measurement range is only limited by the size of grating,its measuring range is greatly increased.The grating-based precision measurement system is very important for high precision measurement of displacement and angle in the field of precision measurement.