Abstract: A high power fiber laser system is configured with a combiner end fiber spliced to a combiner output fiber. The system further includes a light stripper extending along the combiner end and output fibers and configured with sequentially located zones which are provided with respective refractive indices. In a forward propagating direction of light signal, the upstream zone includes polymeric material with the refractive index higher than that of the cladding of the combiner end fiber. This zone is configured to remove the backreflected core guided light bled into the cladding of the combiner through a splice between combiner end and output fibers. The intermediate zone includes polymeric material configured with a refractive index lower than that of the cladding of the combiner output fiber so it can prevent clad guided signal light from decoupling the cladding under the material.

Abstract: An ultra-high power fiber laser system includes a multimode combiner which is configured with a plurality of low mode fibers bundled together and tapering toward its downstream end. A clad mode absorber extends along the tapered downstream end and over a portion of the combiner's output fiber. The absorber is configured with adjacent zones which are provided with respective refractive indices. In a forward propagating direction of signal, the upstream zone includes polymeric material with the refractive index higher than that of the cladding of the combiner end fiber. The intermediate zone includes polymeric material configured with a refractive index lower than that of the cladding of the combiner output fiber. The downstream zone is configured with polymeric material having a refractive index lower than that of the cladding of the combiner output fiber and impregnated with a plurality of light diffusers.

Abstract: A high power fiber laser system is configured with a combiner end fiber spliced to a combiner output fiber. The system further includes a light stripper extending along the combiner end and output fibers and configured with sequentially located zones which are provided with respective refractive indices. In a forward propagating direction of light signal, the upstream zone includes polymeric material with the refractive index higher than that of the cladding of the combiner end fiber. This zone is configured to remove the backreflected core guided light bled into the cladding of the combiner through a splice between combiner end and output fibers. The intermediate zone includes polymeric material configured with a refractive index lower than that of the cladding of the combiner output fiber so it can prevent clad guided signal light from decoupling the cladding under the material.

Abstract: An ultra-high power fiber laser system includes a multimode combiner which is configured with a plurality of low mode fibers bundled together and tapering toward its downstream end. The system further includes a clad mode absorber extending along the tapered downstream end of the combiner and extending over a portion of the combiner's output fiber. The absorber is configured with sequentially located zones which are provided with respective refractive indices. In a forward propagating direction of light signal, the upstream zone includes polymeric material with the refractive index higher than that of the cladding of the combiner end fiber. This zone is configured to remove the back reflected core guided light bled into the cladding of the combiner through a splice between combiner end and output fibers.