title: Gradient-index rod lens with high N.A.
abstract: new gradient-index lens with high numerical aperture has been fabricated by a new ion-exchange technique. In this treatment, a glass rod doped with a highly polarizable ion (dopant A) is immersed into KNO3 salt doped with a medium polarizability ion (dopant B). Dopant B penetrates into the rod and modifies the refractive-index profile of the lens. This new lens has 0.6 N.A. and gives a 1.18-micron spot diam in the light-focusing system. This lens gives good results also in a light source coupling system and is useful in microoptic devices.
authors.affiliation: Nippon Sheet Glass Company, Ltd., Research Laboratory, Konoike, Itami 664, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamagishi
authors.forename: K
authors.initials: K
authors.lastname: Fujii
authors.forename: I
authors.initials: I
authors.lastname: Kitano