高层大气风场探测改型大光程差Sagnac干涉仪全视场角光程差与横向剪切量的精确计算

Exact calculation of the optical path difference and lateral displacement of modified large optical path difference Sagnac interferometer in full view field used in upper atmospheric wind field measurement

提出了一种用于高层大气风场探测的改型大光程差Sagnac干涉仪,论述了其基本原理和分光机理;分析了空间光线在改型大光程差Sagnac干涉仪中的传播路径;利用空间几何方法,通过分析空间直线与其投影之间的关系,给出了入射光线绕入射界面法线旋转360°范围内,从任意方向以任意角度入射时,改型大光程差Sagnac干涉仪的光程差及横向剪切量的精确表达式,较目前文献所报道的只给出入射面与纸平面平行时光程差与横向剪切量的计算具有更加普遍的指导意义.为改型大光程差Sagnac干涉仪的设计、研制提供了重要的理论依据和实践指导,为实现静态、无动镜高层大气风场探测奠定了理论与工程基础.

The shearing principle of modified large optical path difference Sagnac interferometer for upper atmospheric wind field measurement is presented. The exact expression of the optical path difference and lateral displacement in the full view field of modified Sagnac interferometer are calculated by analysing the relation between space beeline and its projection and the notion of ray index at random incidence angle. The theoretical and practical guidance are thereby provided for the study and design of the spatially modulated interference imaging spectrometers.