球透镜的折射率计算与成像分析

Ball Lenses:Calculation of Index of Refraction and Analysis of Image

从Snell定律出发,给出了球透镜折射率的计算公式,并研究了不同折射率情况下球透镜的成像特性和耦合效率。结果表明:折射率为1.57的球透镜具有很好的成像,能够有效地将来自球透镜的光汇聚,但是其耦合效率只有63%;折射率为2.77的球透镜,由于其焦点在球透镜内部,因此通过球透镜的光将产生发散,不能很好成像,且耦合效率较低,最大只有40%,但是通过增加准直系统和折射率为1.57的球透镜后,其耦合效率可以达到70%。

In this paper, calculating formula is given according to Snell law, and the imaging characteristics and coupling efficiencies having different index of refraction are researched. The results indicate that ball lens with n = 1.57 can converge the light effectively and have good image, but its coupling efficiency is 63%. Because its focal spot is in ball lens and the light from it will be diverged, ball lens with n = 2.77 can not image effectively and has 40% coupling efficiency. If the collimating device and ball lens with n = 1.57, its coupling efficiency can reach 70%.