OPTIMUM REFRACTIVE-INDEX PROFILE OF THE GRADED-INDEX POLYMER OPTICAL-FIBER, TOWARD GIGABIT DATA LINKS

The optimum refractive-index distribution of the high-bandwidth graded -index polymer optical fiber (POF) was clarified for the first time by consideration of both modal and material dispersions. The ultimate ba ndwidth achieved by the POF is investigated by a quantitative estimati on of the material dispersion as well as the modal dispersion. The res ults indicate that even if the refractive-index distribution is tightl y controlled, the bandwidth of the graded-index POF is dominated by th e material dispersion when the required bit rate becomes larger than a few gigabits per second. It is also confirmed that the material dispe rsion strongly depends on the matrix polymer and that the use of a flu orinated polymer whose material dispersion [-0.078 ns/(nm km)] is lowe r than that of poly(methyl methacrylate) [-0.305 ns/(nm km)] allows fo r a 10-Gb/s signal transmission. (C) 1996 Optical Society of America