Graded-index plastic optical fiber composed of methyl methacrylate and vinyl phenylacetate copolymers

Graded-index plastic optical fiber whose transmission attenuation is 143 dB/km at 651-nm wavelength was fabricated by heat-drawing the corresponding GI preform rod. This rod is prepared by the interfacial-gel copolymerization technique of methyl methacrylate (MMA) and vinyl phenylacetate (VPAc). The total scattering loss of the GI preform rod is ~60 dB/km at 633 nm. The graded-index profiles of the optical fibers are almost the same as those of the corresponding preforms with cladding sheaths. The index distributions of their core regions are quadratic against the distance from the center axis. The numerical aperture estimated from the index difference is ~0.20.