塞曼激光外差干涉仪的非线性分析及校正

He-Ne激光器施加纵向磁场或横向磁场构成的纵向塞曼激光器和横向塞曼激光器,是激光外差干涉仪最常用的光源。外差干涉仪原理表明,干涉仪所测位移和仪器测得的光电信号的相位变化,是线性关系。而实际上由于光源和光学系统难于达到理想状态,使二者之间产生了周期性非线性,导致纳米、亚纳米测量难以实现。本文分析了引起非线性的原因及其特性,提出了校正和减小非线性的方法,并证实了其有效性。

NONLINEAR ANALYSIS AND IMPROVEMENT OF ZEEMAN LASER HETERODYNE INTERFEROMETER

The He Ne laser in vertical or horizontal magnetic filed forms the vertical or horizontal Zeeman Laser.These kinds of Laser are widely applied in the heterodyne interferometers.The principle of heterodyne shows that the displacement measured by interferometer has the linear relationship with the phase of optical electric signal which detected by electric device.However this linear relationship are not able to reach in real uses as the light source and the optical elements are not ideal,and cause it impossible to use Zeeman Laser in nanometer measuring range.This paper discusses characters of nonlinear,analyses the reason which causes nonlinear,then presents a method by which the nonlinear can be improved,and provides the effectiveness of the method.