| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a obstacle point detecting system of a passive branch type optical fiber line which is capable of accurately detecting obstacle points to be disconnection points and increasing the points of loss of an optical branch line, using a relatively simple constitution. <P>SOLUTION: To output ports of optical couplers 31-1 to 31-16, having two respective input/output ports, individual branch lines are connected, respectively, signal light is input in one input port of each optical coupler via the individual branch lines branched from a star coupler 33 and diagnosis light is input in the rest of input ports via diagnosis light lines 32-1 to 32-8. By this constitution, branch lines where one diagnosis light is simultaneously transmitted is limited to two lines. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
