Patent ID: 7428354
Filing Date: 2008-09-23
Classification: H04B

Abstract:
1. An optical transmission-path fault-detection system comprising: a first excitation light-beam source connected by a first optical transmission path to an optical amplifier for transmitting a light beam to said first optical-transmission path, wherein the first excitation light-beam source is an excitation light source to provide excitation light to the optical amplifier so that a signal light beam is optically amplified by the optical amplifier in accordance with the provided excitation light; first optical-detection means for detecting the light beam which is transmitted from said first excitation light-beam source and input via said first optical-transmission path, then to said optical amplifier and then to a second optical-transmission path, to said first optical-detection means; and first fault-determining means for determining, when a light beam level detected by said first optical-detection means is lower than a predetermined level, that a fault has occurred in one of said first optical-transmission path and said second optical-transmission path, and determining, when the light beam level is at or higher than the predetermined level, that said first optical-transmission path and said second optical-transmission path are normal; and stop-instruction means for instructing said first excitation light-beam source, when determining by said first fault-determining means that the fault has occurred in one of said first optical-transmission path and said second optical-transmission path, to stop transmitting said light beam.