一种Wollaston式偏光棱镜分束特性的研究

摘要

为了对一种修正式对称分束Wollaston棱镜的分束特性进行系统分析,利用折射定律和菲涅耳公式,以632.8nm波长为例,给出了出射光与水平方向的夹角随修正角、结构角之间的变化关系曲线、光强分束比随结构角的变化关系以及入射角对棱镜分束角和出射光束对称性的影响曲线.结果表明,通过对出射端面的修正可以实现Wollaston棱镜的严格对称分束;o光、e光分束角主要取决于棱镜结构角,受棱镜修正角影响较小;光强分束比随结构角的增大变化幅度较小;当光线以小角度入射时,入射角主要影响棱镜分束角对称性;入射角在-3°~3°之间变化时,两出射光线的不对称度小于6°,可以保证较好的对称分束效果.该研究为该棱镜的设计和应用提供了理论指导.%In order to analysis systematically the splitting characteristics of a Wollaston-type symmetric beam-splitting prism,by using refractive formula and Fresnel formula and taking 632.8nm for example, relationship curve among the angle of emergent light to the horizontal direction,deviation angle and structure angle,relationship curve between intensity splitting beam ratio and structure angle,relationship curve among incident angle,splitting beam angle of the prism and emerging light symmetry were gotten. The results show that, strict symmetric beam can be achieved through the correction of output face of Wollaston prism. Splitting angles of o light and e light mainly depend on the prism structure angle. The effect of deviation angle is smaller. The changing magnification of beam splitting ratio with the increase of structure angle is small. When the incident angle is small, it has main effect on the symmetry of prism splitting angle. When incident angle changes between-3°and+3°, the asymmetry degree of two beam is less than 6°,which can guarantee good effect of symmetry beam splitting. The study provides a theoretical guidance for design and application of the prism.