Abstract: A system detects potentially dangerous conditions, prevents damage to optical components, and prevents humans from being physically harmed by stray pumping light. Optical systems employing distributed amplification such as Raman amplification utilize pumps having high output powers. These high output powers create dangerously high power densities in the optical fiber. If a connection is imperfect a hot spot may develop and the connection damaged by the pumping light. Fiber damage, disconnections and component degradations or failures may also permit the pumping light to escape the intended path and cause physical harm to humans as well as equipment. Pumping light backreflections caused by such imperfect connections, degraded/failed components, and fiber damage are detected. A controller compares the backreflection amount against a threshold to determine whether a precautionary measure should be taken such as shutting down the pump, decreasing pump power to a safe level or setting a maintenance flag.

Abstract: A system prevents damage to at least one component of a laser apparatus that includes a laser that emits a light signal of increasing power during power up and at least one connector that receives the light signal from the laser and reflects at least a portion of the light signal when an imperfect connection exists. The system includes a detector and a monitoring circuit. The detector detects the reflected light signal from the connector. The monitoring circuit receives the reflected light signal, determines an amount of power in the reflected light signal, calculates a ratio of the power of the light signal emitted by the laser to the power in the reflected light signal, compares the ratio to a predetermined threshold to determine whether the imperfect connection exists, and shuts down the laser when the imperfect connection exists.