| 摘要 |
PURPOSE:To obtain optical fiber having high resistance to radiant rays by subjecting a core-shell type plastic optical fiber constituted of a resin for the shell having a smaller refractive index than a refractive index of an acrylic resin for the core to oxygen diffusion treatment under pressure, or subjecting further to radiant rays treatment. CONSTITUTION:A core of a core shell type optical fiber is constituted of an acrylic resin, which is pref. a homopolymer of methyl methacrylate or a copolymer of methyl methacrylate contg. >=50wt.% methyl methacrylate for the purpose of maintaining high transmittance of light. Suitable resin for constituting the shell is one having high transparency and smaller refractive index than an acrylic resin for constituting the core. The oxygen diffusion treatment is performed most pref. under pressure above atmospheric pressure in a gas having higher oxygen content than air. The product may be further treated with radiant rays after the completion of the oxygen diffusion treatment. Thus, an optical fiber having high resistance to radiant rays is obtd. |
