激光干涉快速超精密测量残余累计误差研究

Study on Residual Cumulative Error in Fast Ultra-precision Measurement by Laser Interference

随着激光外差干涉测量速度的提高,其存在的原理性误差严重影响测量精度。通过对激光外差干涉原理上产生残余累计误差的机理进行理论分析,给出影响误差大小的因素,并进行相应的仿真验证,提出误差修正方案,应用数值分析的方法,通过获取激光外差干涉的实时速度,实现误差补偿。仿真结果表明,此方法能够有效地减小残余累计误差,当最大测量速度为 1 m/s、最大位移为 3 m时,能够消除17.7 nm的残余累计误差,而且能消除其累计现象。

With the improvement of measurement velocity in laser heterodyne interference, the theoretical error of laser heterodyne interference seriously restricted the accuracy of measurement. The principle of laser heterodyne interferometer was analyzed, the residual cumulative error in theory was derived, the factors influencing the error were analyzed, and the error was emulated. With the real-time velocity of laser interference obtained, a novel error correction scheme was provided to reduce the residual cumulative error in project. Simulation result shows the residual cumulative error that is up to 17.7 nm can be reduced by the method when the highest speed is up to 1 m/s and the displacement is up to 3 m, and the cumulative is canceled.