Selfoc microlens with a spherical surface.
This paper presents the light-focusing properties of a gradient-index rod lens with a spherical end surface which aims at increasing numerical aperture and decreasing lens aberration. Optimum refractive-index profiles for obtaining a smaller focused spot are derived, and the increase of numerical aperture is clarified. Experimental results are described; the Selfoc microlens with a spherical end surface realizes a focused spot below 2 microm in diameter.
Yamamoto
N
N
Nippon Sheet Glass Company, Ltd., Research Laboratory, Konoike, Itami 664, Japan.
Nishi
H
H
Nishizawa
K
K
Kitano
I
I