T. Xu et al. A dual-stage correction approach for high-precision phase-shifter inFizeau interferometers.
发布人:管理员  发布时间:2024-03-27   浏览次数:146

DOI: 10.1016/j.optlaseng.2024.108205


Abstract


This paper proposes a dual-stage correction approach for a high-accuracy phase-shifter in Fizeau laser interferometers, effectively reducing the phase shift errors in PSI (Phase-Shifting interferometry) and improving the precision of surface profile measurements. The precision of PSI depends on the displacement accuracy of the reference mirror, and the function of the phase shifter is to drive the reference mirror to generate wavelength- level displacements with nanometer-level accuracy. The first-stage correction aims to reduce the nonlinearity error of the reference mirror by ULPS (Ultra-High Linearity Phase Shifter). The second-stage correction aims to reduce the average velocity error and plane velocity uniformity error of the reference mirror by AVIC (Auto Velocity Iterative Correction). The experimental results indicate that, after the first-stage correction, ULPS exhibits a 0.05 % nonlinearity, a 2.5 nm repeatability, and a 0.2 nm resolution under a load of 20 kg, and its nonlinearity surpassing all phase-shifters documented in the literature. After the second-stage correction, the average velocity error and plane velocity uniformity error of the reference mirror are reduced to 0.07 %.


文章摘要


这篇论文提出了一种用于菲索激光干涉仪中高精度相移器的双阶段校正方法,有效地减少了PSI(相移干涉测量)中的相位偏移误差,并提高了表面轮廓测量的精度。PSI的精度取决于参考镜的位移精度,相移器的作用是驱动参考镜产生纳米级精度的波长级位移。第一阶段校正旨在通过ULPS(超高线性相移器)减少参考镜的非线性误差。第二阶段校正旨在通过AVIC(自动速度迭代校正)减少参考镜的平均速度误差和平速度均匀性误差。实验结果表明,在第一阶段校正后,ULPS显示出0.05%的非线性,2.5纳米的重复性和0.2纳米的分辨率,负载为20公斤,其非线性超越了文献中记录的所有相移器。在第二阶段校正后,参考镜的平均速度误差和平速度均匀性误差降低到0.07%


图片摘要

图一:移相器双阶段校正方法

第一阶段减少参考镜的非线性误差EL。第二阶段减少参考镜的平均速度误差EA和平速度一致性误差EP。在菲索干涉仪中,如果系统发生变化,如温度变化或镜头调整,将重新激活第二阶段校正以进一步减少EAEP


亮点


本文提出了一种基于ULPS(超高线性移相器)和AVIC(自动速度迭代校正)的移相器校正方法,用于菲索激光干涉仪,有效地减少了相移误差,提高了菲索激光干涉仪的测量精度。ULPS是一种配备有三个高精度电容传感器的机械相移器。ULPS实现了0.12纳米的分辨率,0.05%的非线性,2.5纳米的重复性,以及在20公斤负载下10微米的最大行程。AVIC是一种基于图像的移相器速度校正方法。它有效地抑制了由移相器引起的误差,包括参考镜的平均速度误差和平速度一致性误差。此外,AVIC可以帮助移相器适应各种环境和系统变化,包括温度变化和镜头更换。