OPTICAL FIBER CONNECTING DEVICE, OPTICAL COUPLING METHOD FOR OPTICAL FIBER, AND MANUFACTURE OF OPTICAL FIBER CABLE AND OPTICAL ELEMENT

摘要

PROBLEM TO BE SOLVED: To reduce the connection loss between optical fibers if a transmission- side and a reception-side optical fiber have a different in core diameter or have their axes misaligned. SOLUTION: The large-diameter end surface of a transparent optical rod 5 which is in the shape of a frustum of a circular cone is a photodetection-side end surface 6 and the small-diameter end surface is a light projection side end surface 7. The photodetection side end surface 6 is made to abut against the end surface of a transmission-side optical fiber 1 and has a diameter larger than the core diameter of the transmission-side optical fiber 1. The light- projection side end surface 7 is made to abut against the end surface of a photodetection-side optical fiber 2 and has a diameter smaller than the core diameter of the photodetection-side optical fiber 2.