Studies on the light-focusing plastic rod. 18: Control of refractive-index distribution of plastic radial gradient-index rod by photocopolymerization

The refractive-index distribution patterns obtainable by the photocopolymerization of ternary monomer systems were predicted with the help of the mechanism for forming a radial gradient index reported by Ohtsuka and Koike. On the basis of this prediction, we successfully fabricated a convex lens, a concave lens, and a fiber with the W-shaped index distribution expected of an optical fiber with low modal dispersion. It was theoretically and experimentally confirmed that the index distribution of the rod by the photocopolymerization of a ternary monomer system could be widely controlled.