OPTICAL COMMUNICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To efficiently optically couple an optical fiber having a large bore diameter and a photodetector having a small bore diameter with a simple configuration. SOLUTION: The optical communication system is provided with the plastic optical fiber 1 and an optical communication module 2A, in which the fiber 1 has a spherical end face 11 and the numerical aperture of the radiation light emitted from the end face 11 is≤0.35. The fiber 1 is installed at the module 2A in such a manner that the photodetecting surface of the photodetector 21 comes to a position of a distance (d) from the apex of the end face 11 of the optical fiber. When the diameter of the optical fiber is defined as D, the radius R of curvature of the spherical end face as r*D, the refractive index of the core of the optical fiber as (n), and the refractive index of the substance existing between the spherical end face of the optical fiber and the photodetector as n1, the distance (d) is 0