三元结构双反射平行分束偏光镜设计

为了节省冰洲石晶体材料，并实现两束偏振光的平行输出，采用冰洲石与光学玻璃组合的方法，给出一种双反射形式平行分束偏光镜的新设计。该棱镜为ZBaF3玻璃中间加冰洲石晶体薄片的三元结构，采用溴代萘胶合；选择合适的结构角，令电矢量振动方向相互垂直的两束偏振光分别在前胶合面、后端面发生全反射，并垂直上端面平行出射。实验测试表明，棱镜的透射比高于80%，消光比优于10-3。该设计在节省冰洲石晶体前提下，保持了良好的性能。

Ternary bireflective parallel beamsplitting polarization prism

In order to save iceland and output two parallel polarized beams, a new type of bireflective parallel beam splitter combined of iceland and glass is designed. The prism is made of ZBaF3 glass, between which is iceland, using bromonaphthalene as the glue. Selecting the suitable structure angles, two polarized beam whose directions of electric vector are orthogonal can escape vertically to the same exit widow after their total reflection on the front cemented surface and the back surface respectively. The experiments indicate that the transmittance of the prism is more than 80%, and the extinction ratio is better than 10-3. Therefore, the prism still has good performance on the premise of saving iceland greatly.