| 摘要 |
PROBLEM TO BE SOLVED: To suppress the connection loss of a plastic optical fiber and a photodetector to a lower level by interposing an optical repeater element of the core diameter successively diminishing from an optical fiber side toward a receiving optics side between the end face of the plastic optical fiber and the light receiving surface of the receiving optics. SOLUTION: The optical repeater element 20 is constituted by coating the outer periphery of the core part 22 with a clad part 23. The core part 22 has the shape of the outside diameter size successively diminishing from its base end side toward the front end side within the optical repeater element 20. The refractive index distribution at the section of the core part 22 is so set that the refractive index thereof is successively lower form its axial center toward the outer periphery like the core of the graded index optical fiber. In addition, the refractive index along the axial direction of the core part 22 is so set as to be successively lower from the base end side toward the front end side of the optical repeater element 20. The clad part 23 has the specified refractive index smaller than the refractive index in the any place of the core part 22. |
