Patent ID: 7657175

Claim:
An optical communication device for detecting defects in optical fibers, comprising: active optical output means for outputting a first optical signal; standby optical output means, provided as a substitute for the active optical output means, for outputting a second optical signal; an active optical fiber connected to the active optical output means to carry the first optical signal; a standby optical fiber connected to the standby optical output means to carry the second optical signal; optical router means connected to the active and standby optical fibers, the optical router means being adapted to output the first optical signal to a subsequent stage and also to output part of the first optical signal from the active optical output means to the standby optical output means through the standby optical fiber in a direction opposite to the second optical signal from the standby optical output means; and defect detector means for detecting a defect in the standby optical fiber, based on a light level of the first optical signal output from the optical router means to the standby optical output means.