In this paper, we investigate a 19 1 tapered fiber bundle (TFB) pump combiner for high power fiber lasers theoretically and experimentally, based on the twist method. Theoretically, we analyze the influence of the taper length, taper ratio and twist angle on the performance of a 19 1 TFB combiner by using the beam propagation method. Then, a 19 1 all-fiber combiner is fabricated experimentally, with input fibers and output fiber having core/clad diameter of 220/242 μm (numerical aperture (NA) = 0.22) and 30/600 μm (NA = 0.06/0.46) respectively. The transmission efficiency of each port is higher than 98.6% and the average efficiency of all 19 ports is 99.3%. The combiner achieved an output power of 1.5 kW with transmission efficiency of 99.3% when tested with four ports of 976 nm laser diode. To our best knowledge, this is the first time that 220/242 μm (NA = 0.22) multimode fibers act as the pump fibers of a 19 1 end-pumping combiner.

在本文中，我们基于扭曲方法，从理论上和实验上研究了用于高功率光纤激光器的19 1锥形光纤束（TFB）泵浦组合器。从理论上讲，我们使用束传播方法分析了锥度长度，锥度比和扭曲角对19 1 TFB合成器性能的影响。然后，将19 1全光纤组合器实验制成，与输入光纤和二百四十二分之二百二十零具有输出光纤的芯/包层直径μ米（数值孔径（NA）= 0.22）和六百分之三十零μm（NA = 0.06 / 0.46）。每个端口的传输效率高于98.6％，所有19个端口的平均效率为99.3％。当使用976 nm激光二极管的四个端口进行测试时，该组合器实现了1.5 kW的输出功率和99.3％的传输效率。据我们所知，这是第一次发现242分之220 μ米（NA = 0.22）的多模光纤作为一个19 1端面泵浦组合器的泵浦光纤。