| 摘要 |
<p>PROBLEM TO BE SOLVED: To enhance an optical power by a method, wherein pumping light generated by a pumping part is multiplexed, incident signal light from a rear stage is divided according to its wavelengths, multiplexed output light outputted to the pumping part is partly reflected, and the rest of the multiplexed output light is outputted as pumping light. SOLUTION: Pumping light generated by a pumping part 200 is stabilized through an external feedback, reflected in wide bandwidth from a wide bandwidth reflector 230, and divided by a multiplexer 220 according to wavelengths. Diodes provided to the pumping part 200 are possessed of the same wavelength band and selected by reflected light which impinges from the multiplexer 220. That is, pumping light whose wavelength is determined through feedback is generated and sent to single mode optical fibers linked to the multiplexer 220. The pumping light passes through a polarized fiber loop 234 through the intermediary of an optical coupler 232. At this point, light incident on the optical coupler 232 travels in the direction of 'a', without change in phase but travels in the direction of 'b', shifting in phase by an angle of 90 deg..</p> |
