Patent ID: 9140856
Filing Date: 2015-09-22
Classification: G02B

Abstract:
1. A multimode (“MM”) high power combiner, comprising: a plurality of passive low mode (“LM”) fibers guiding respective outputs, the LM fibers being bundled together to define a tapered downstream end of a bundle, the downstream end having a core guiding combined MM signal light in a propagating direction, and at least one cladding; a MM combiner output fiber butted to the tapered downstream end so as to define a splice therebetween, the output fiber having a cladding surrounding a core which guides the MM signal light, the MM signal light being incident on a workpiece which partially reflects the incident MM signal light so that the reflected MM signal light is coupled into the core and cladding of the output fiber in a counter-propagating direction; and a clad mode absorber (“CMA”) surrounding the downstream end of the bundle and extending over a part of the combiner output fiber, the CMA being configured with: