| 摘要 |
PURPOSE:To detect the transmission direction in an optical line by bending the optical line until emission loss light leaks out while maintaining the quality of a light signal, and providing >=2 emission loss light detectors outside the bent part. CONSTITUTION:The object optical fiber 1 is bent by a dedicated bending jig without spoiling the quantity of the light signal, and light signals shown by a solid line and a broken line are made to leak out of the bent part 1a. The light detectors 2 and 3 provided outside the bent part 1a detects the emission loss light beams 4 and 5 shown by the solid line and broken line. At this time, the detectors 2 and 3 are arranged where they can be photodetected most intensely. Namely, they are arranged at angles alpha and beta to the bending center line of the bent line 1a. Consequently, the transmission direction in the optical fiber 1 can be detected without interrupting the function of a communication line. |
