| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical branching device for controlling optical output only for an abnormal port. SOLUTION: Photo diode PDa-PDn receive reflected light emitted from the end surface of an optical fiber and transduce it into electric signals. Reflected light detection control parts 10a-10n judge voltage value of the electric signal and when the value exceeds predetermined reference value, it is considered that the reflected light is generated and a dejection control signal is provided. Exterior modulating parts 20a-20n control strength modulation of an optical signal by receiving the detection control signal and lower and output level of the optical signal to an abnormal port which has the optical fiber which generated the reflected light. |
