依据速率方程和边界条件,对高功率多点抽运全光纤激光器进行了研究.通过自制的级联侧面泵浦耦合器搭建全光纤激光器,级联耦合器的单点泵浦效率为96%,泵浦传输损耗为10%,信号光损耗分别是0.18 dB和0.87 dB;线性谐振腔结构中：前向抽运的光-光转换效率为69%,低于后向抽运中70%的光-光转换效率,与理论分析一致;双向泵浦方式中,在单臂输入975 nm泵浦功率为110 W的条件下,激光功率输出为311 W,中心波长为1 080 nm,光谱宽度为1.6 nm,光-光转换效率为70%,光束质量约为1.3.激光器性能稳定,若增加单臂泵浦功率或级联泵浦耦合器个数,可获得更高功率的激光输出.

In order to research high-power multi-position-pumped fiber lasers,the theoretical analysis was presented based on the rate equations and boundary conditions of Yb-doped double-clad fiber lasers. All-fiber laser is built with the self-made cascaded couplers. In the experiment,the pump efficiency of a single coupler is 96%,pump transmissiom loss is 10%,signal loss of the couplers are 0.87 dB and 0.18 dB respectively. In the structure of linear cavity,the optical conversion of forward pump is 69%,lower to the backward pump of 70% optical conversion,consistent with theoretical simulations; in the two-end pump,single input pump power of 975 nm is 110 W,the output power is 311 W with the central wavelength of 1 080 nm,spectral width is 1.6 nm,the optical-optical conversion is 70%,M2～1.3. The results have shown that the output power of laser will continue to increase with the increase of the pump power or the number of couplers.