| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a bridge fiber, a combiner, and a fiber laser device that allows easily reducing failure of a pumping light source caused by return light.SOLUTION: A bridge fiber 30 includes a core layer 31 and an outer layer 32 having a higher refractive index than the core layer 31 and covering the outer peripheral surface of the core layer 31. The outer layer 32 is surrounded by, for example, an atmosphere having a refractive index lower than the refractive index nof the outer layer 32. An area AR1 of the outer layer 32 at one end face of the bridge fiber 30 is an area that is to be optically coupled to a core end face of each of a plurality of pumping light inputting optical fibers 20, whereas an area AR2 of the core layer 31 at the other end face of the bridge fiber 30 is an area that is to be optically coupled to a core end face of an amplification optical fiber 40.</p> |
