OPTICAL FIBER AMPLIFIER AND OPTICAL TRANSMITTER

摘要

PURPOSE: To conduct fault monitor with respect to an optical fiber amplifier in the standby state without giving adverse effect onto a substantial transmission signal regardless of redundant configuration. CONSTITUTION: A PD module 29 detects a level of an optical signal being an output of an optical fiber amplifier 13 and an error amplifier 31a and an LD drive circuit 32 control a level of a stimulated light generated by the LD module 24 so that the level has a prescribed relation to a prescribed reference voltage. A 1st reference voltage V1 generated from a reference voltage generating circuit 31b in the active state and a 2nd reference voltage V2 generated from a reference voltage generating circuit 31c in the standby state are selected by an output interrupt control circuit 31d.