CONNECTING METHOD OF OPTICAL FIBER ENDS TO EACH OTHER BY MATCHING LIQUID IN METHOD FOR WELDING AND CONNECTING OPTICAL FIBERS TO EACH OTHER

摘要

PURPOSE:To set an exact source level and to enable optical fiber connection at a low loss by connecting optically the end faces of the optical fibers via a matching liquid while discriminating the connecting conditions in several stages. CONSTITUTION:The end 2A of one optical fiber is slightly moved stepwise toward the other end 2B by a driving system 7 in the stage of connecting optically the end faces of the optical fibers to each other by the matching liquid. An optical signal is fed from this slight light source 9 to the optical fibers 1A, 1B and a photodetector 10, by which the photodetection power is detected. The space between the end faces is narrowed and the photodetection power P1 is attained just before contact with the matching liquid. The level of the power decreases to the photodetection power P2 as the end faces are bridged by the matching liquid when the end faces are further advanced stepwise. The matching liquid between the end faces converge to a stable state on succeeding stepwise advancing and the level of the power increases to the photodetection power P3. The attainment of the optical connection between the end faces by the matching liquid is discriminated when P3-P1 attains =0.3dB, by which the connection is completed.