Optical transmission bandwidth of poly(methyl methacrylate)-Based graded-index optical fibers with microscopic heterogeneities

We experimentally evaluated the influence of microscopic heterogeneities on light transmission characteristics of poly(methyl methacrylate)-based graded-index plastic optical fiber (GI POF) fabricated by interfacial gel polymerization. The GI POF had few differential mode attenuation because the fabrication method results in no steep refractive index change of core-cladding boundary. On the other hand, the transmission bandwidth was significantly affected by mode coupling. These results suggest that the mode coupling in the GI POF can be predominantly induced by density-fluctuation-induced volume scattering.