基于相控外差干涉技术的纳米定位方法的研究

Research of nanopositioning method based on phase-control heterodyne interferometric technique

针对工业领域和计量界对定位精度要求的提高,提出了一种基于迈克尔逊干涉仪反向特性的定位控制方法。该方法采用相位锁定控制和外差干涉技术来完成位置测量和控制。在严格控制实验环境条件下,得到了步距值为5 nm的双向步进位移。步距值的不确定度为8×10-9 nm,位移重复性误差小于1 nm。该定位方法的测量尺寸可直接溯源至长度标准,并且采用光电步进相移法可克服压电陶瓷的非线性和蠕变的机械缺陷。该方法在系统环境控制条件下适用于毫米行程位移,可应用于纳米计量和超精密加工等领域。

Aiming at the requirement of higher positioning accuracy in industry and metrology fields,we propose a position control method based on reverse property of Michelson interferometers.This method employs phase-locked control and heterodyne technique to perform position measuring and control.Under strictly controlled experiment environment,the back and forth displacement with step value of 5 nm is achieved.The intrinsic uncertainty of the step value is 8×10^-9 nm and the repeatability of the displacement is less than 1nm.Using this method,the measurement value of the displacement is traceable to the length standard.Furthermore,the mechanical defects of the piezoelectric actuator,such as nonlinearity and creep,are overcome through using the optoelectronic phase-shifting method.The proposed method could be used in millimeter range displacement measurement in a controlled system environment,and applied to numerous applications in nanometrology and ultraprecision machining.