Demonstration of >5kW emissions with good beam quality from two different 7:1 all-glass fiber coupler-types

Abstract

We report on two low-loss 7:1 single-mode to multi-mode fiber coupler-designs generating more than 5 kW of output power. These all-glass fiber-optical devices have the objective to keep the brightness at its theoretical maximum and the heat load at its technical minimum. To the best of our knowledge, regarding all-fiber geometrical combined power generation, beam quality and heat stability, the presented results had never been reported before.