为了了解Wollaston棱镜正反向使用时分束角及分束角的对称性, 采用数学运算和实验测试相结合的方法, 进行了理论分析和实验验证, 取得了较为理想的数据。由分析可知, Wollaston棱镜正、反向分束角及分束角对称性不同是因为反向入射时第1块棱镜中的o光在第2块棱镜中成为e光波时, 其光矢量振动方向和晶体光轴不平行, 对应的不再是主折射率所致。结果表明, Wollaston棱镜正向使用时的分束角略大于反向入射时的分束角, 且Wollaston棱镜结构角越大, 入射波长越短, 则正、反向分束角的差值越大。

In order to find out the forward and backward splitting angles of a Wollaston prism and their symmetry, satisfactory data were obtained by combining mathematical calculations and experimental test. Analysis shows that the main reason of the symmetry difference of the splitting angles is that the o light incident on the first prism becomes e light on the second prism and then does not parallel to the optical axis of the crystal, no longer is caused by the principal refractive indices. The results demonstrate that the splitting angles becomes slightly larger when it is used positively than negatively. Moreover, the wavelength gets more and more shorter as long as the angle of the prism’s structure became larger. Besides, the difference value between forward and backward splitting angles will get larger too.