An optimum index profile offering the highest bit rate communication was formed in a poly methyl methacrylate (PMMA)-based graded-index plastic optical fiber (GI-POF) by modifying the polymerization process. The interfacial-gel polymerization process we have proposed to fabricate the PMMA-based GI-POF is capable of forming a nearly optimum refractive index profile. However,the theoretically calculated bandwidth from the measured index profile was reduced compared with the GI-POF having optimum index profile. In this paper,we report how to obtain a PMMA-based GI-POF having exactly the optimum index profile. The bandwidth of this ideal GI-POF was experimentally measured and the very high bandwidth of 2.88 GHz even for a 150-m fiber length was confirmed. The calculated bandwidth agreed well with the experimentally measured one. These results indicate that very low modal dispersion can be expected in a GI-POF fabricated by the modified interfacial-gel polymerization process.
Takaaki Ishigure, Sho Tanaka, Eiji Kobayashi, and Yasuhiro Koike, "Accurate Refractive Index Profiling in a Graded-Index Plastic Optical Fiber Exceeding Gigabit Transmission Rates," J. Lightwave Technol. 20, 1449- (2002)