衍射光栅超精密位移定位检测新方法

A New Method Based on Diffraction Grating for Ultra-Precision Displacement Detection and Positioning

光栅干涉仪测量是精密位移检测系统中常用的检测方法,具有较高的检测分辨率。为进一步提高光栅干涉仪位移检测分辨率,通过对光栅干涉条纹信号的分析,提出了一种基于衍射光栅相位移动的超精密位移定位检测新方法。采用衍射光栅作为测量元件,通过在经典的衍射光栅位移检测系统中加入光电传感器的相位运动,改变衍射光栅系统的接收相位。其方法是调整光栅干涉仪系统,使得传感器接收视场中只有两个条纹;在目标定位运动台的最后定位阶段,使接收系统的光电传感器在检测视场的两个干涉条纹间进行移动,即改变了光栅干涉仪的接收相位。这种位移检测方法突破了检测元件本身的物理限制,在理论上可以获得亚纳米级以上的超高位移检测分辨率。依据相位移动原理,搭建了具有相位移动功能的光栅干涉仪超精密位移检测定位系统。通过定位检测试验证明了所提方法的有效性。

The grating interferometer measurement is the commonly used detection method for precision displacement detection system,and it features higher detecting resolution; in order to further improve the detecting resolution,through analyzing the interference fringe signal of grating,a new method based on diffraction grating for ultra precision displacement detection and positioning is proposed.By adopting diffraction grating as the measuring component,through adding phase movement of photoelectric sensor into the diffraction grating displacement interferometer system,the receiving phase of the diffraction grating system is changed.With this method,the interferometer system is adjusted to only have two fringes,in the final positioning stage of the target positioning motion bench; the photoelectric sensor in the receiving system is moving between two of the interference fringes,so the receiving phase of the grating interferometer is changed.This method breaks through the physical limitations of the detecting component; theoretically,the detection resolution above sub-nanometer can be obtained.In accordance with the principle of phase moving,the grating interferometer ultra-precision displacement detection positioning system with phase shift function is set up.The effectiveness of this method is proved through positioning detection tests.