激光外差干涉非线性误差的测量方法

The Method to Measure the Nonlinearity in Laser Heterodyne Interferometer

摘要: 为了调整激光外差干涉光路中的光学元件,减小或抑制测量非线性误差,研究了非线性误差测量的机理和方法.基于对激光外差干涉测量信号的频谱分析,提出了非线性误差的测量方法.根据建立的非线性误差与测量信号幅度之间的模型,计算出非线性误差一次谐波和二次谐波的大小,实现非线性误差的精确测量.实验结果表明,该方法可以有效地测量激光外差干涉的非线性误差.

Abstract: To reduce or restrain the nonlinearity in laser heterodyne interferometer via adjusting optical component,the mechanism and the method of measuring nonlinearity need to be researched.Based on the spectrum analysis of the measurement signal,a method to measure the nonlinearity is proposed.With the model of the amplitude relationship between the nonlinearity and measurement signal,the first harmonic nonlinearity and the second harmonic nonlinearity are counted.Then,the nonlinearity is measured accurately.The experimental result shows that the method can measure the nonlinearity accurately and can easily be adopted.