单频激光干涉仪非线性误差优化方法研究

摘要

为减小非线性误差对单频激光干涉仪测量精度及稳定性的影响,分析了引起其非线性误差的各种因素.利用琼斯矩阵推导出该系统光学参量的数学表达式.采用常规的优化调校方法提高系统精度会带来其它参数性能降低.提出改善单频激光干涉仪性能的最优控制优化调校方法.实验结果表明,采用该调校方法,使单频激光干涉仪信号的正交性、干涉条纹对比度和灵敏度均得到了一定程度的优化,干涉条纹对比度vimax,o可达到0.97,并且两路信号对1/8波片转角的4倍周期也变为2倍周期.%To decrease the influence of the nonlinearity error on accuracy and stability of single-frequency laser interferometer, the factors are researched. Based on the Jones matrix, the optical parameters of the system are expressed. The optimal control adjustment to improve single-frequency laser interferometer is described. Experimental results show that the ordinary adjustment is limited to improve the system accuracy. But the orthogonality of signals, interference fringe contrast and system sensitivity are improved by optimal control adjustment The interference fringe contrast vimax, o achieve to 0. 97, and the four periods of two signals turn into two periods which 1/8 wave plate is revolved.