Step bulk arrangement of 19 fiber laser collimators for directed energy applications

Abstract

We designed an arrangement of 19 high-power fiber laser collimators on an aluminum step bulk in coherent combination for use in directed energy applications. Strong environmental turbulence degrades coherent beam combining advantages; therefore, we only consider low-turbulence levels. The combining elements are single mode 3 kW high-power fiber lasers, which are collected by 19 right-angle prisms in two concentric hexagonal rings for combination. With this configuration, a high combining efficiency of 88%, a high filling factor up to f = 0.9 and lower cost production of the beam combining process are possible.