梯度折射率球透镜的制备及其光线轨迹测试

自麦克斯韦鱼眼透镜理论模型提出后,长期以来学术界一直以为它只是一种绝对光学仪器,在实践中并没有应用的可能。但通过对麦克斯韦鱼眼微球透镜的理论研究表明,在一定条件下,它具有良好的成像性能和耦合效率。根据菲克定律推导出梯度折射率球透镜的折射率分布函数。并且熔制了含Li+硅酸盐玻璃和采用槽沉法以及Na+/Li+离子交换法制备直径为0.3—3.0mm的梯度折射率球透镜。通过干涉法测得了梯度折射率球透镜的折射率分布曲线,并研究了光线通过梯度折射率球透镜的轨迹。研究结果表明:在590℃,离子扩散系数为3.07×10-6mm2/s;所制备的梯度折射率球透镜的折射率分布是抛物线分布,并且和理论分析相吻合;梯度折射率球透镜的光线轨迹满足椭圆方程。

Fabrication of gradient refractive index ball lenses and measurement of the race trace

The theoretical model of the Maxwell fish eye sphere lens has long been regarded as an absolute optical instrument without practical application since it was proposed.But the study on the theory of Maxwell fish eye microspheric lens shows that on certain condition it has fine image formation ability and coupling efficiency.Based on the Fick's diffusion equations,the distribution function of refractive index of gradient refractive index ball lenses(GRIN ball lenses) is derived.Lithium containing silicate glass is fabricated and GRIN ball lenses(GBLs) which diameters are from 0.3mm to 3.0mm are made by ion exchange and the sagging method in sodium nitrate.Radial refractive index profiles of these GRIN ball lens are measured by interferometer.Results show that the diffusion coefficient at 590℃ is 3.07×10-6mm2/s.The distribution of the index of refraction is parabolic curve and in concordance with the theoretical analysis.The ray trace of a GBL is accord with elliptic equation.