大量程光栅位移测量累积误差的修正

摘要

The cumulative error correction method through auto-measuring grating pitch is proposed.The grating pitch measurement is based on the high order cumulants to estimate time delay between two moiré signals of grating sensor,this method can realize the measurement of each grating pitch,and reduce cumulative error by correcting each grating pitch error,which is the foundation for the realization of long range and high precision measurement.The experiment uses the grating sensor with the length of 500 mm,and 50 lines/mm,which includes the 25000 grating lines,and realizes grating pitch measurement resolution of 3nm,which reaches to the nanometer level.Anti-interference ability of the method is strong,which is suitable for field application on production.%提出了一种自动测量光栅栅距修正累积误差的方法.栅距测量是基于高阶累积量估计光栅传感器输出的两路莫尔条纹信号的时间延迟而得到的,该方法能够实现每个栅距的测量,通过对每个光栅栅距的误差进行修正来减少累积误差,为大量程高精度测量奠定了基础.实验采用长为500 mm的50线/mm的光栅传感器,该传感器包含栅线25 000条,实现栅距测量分辨力为3 nm,达到了纳米级测量.该方法抗干扰能力强,适合在生产现场应用.