含Li^+的径向梯度折射率棒透镜的研究

RADIAL GRADIENT INDEX ROD CONTAINING Li^+

研究发现在硼硅酸盐系统玻璃中 ,利用 Li+/Na+离子交换来制取径向梯度折射率( GRIN)棒透镜时 ,基质玻璃中重要的成分 L i2 O含量对径向 GRIN棒透镜的象差和数值孔径值有着明显的影响 ,并着重分析和讨论了实验中 Li2 O含量对径向 GRIN棒透镜中折射率分布、数值孔径及象差影响机制 .进一步指出实验中 Li2 O含量存在一个最佳值 ,既能够满足径向

In this paper,the relation between the radial gradient index rod lens obtained by Li +/Na + ion exchang and alkali metal oxide(Li 2 O) contents in their mother glass composition is studied.It is observed that Li 2 O contents is one of the important factors which affect the performance of the rod lens.Firstly the more Li 2 O contents become the more the quality of Li + which can exchang with Na + in molten salt become,afterwords the numerical apeture of rod lens improved,at the same time because of the difference of ion exchang rate between the middle region and marginal region of the rod lens,the refractive index profile of the radial GRIN rod lens begin to deviate from desired n 2(r)=n 2 0sech 2(gr) function.When the Li 2 O contents is beyond 14mol%,it is easy to emerge the platform at the marginal of rod lens,this causes the numerical apeture decreases and the quality of image deteriorates rapidly.