侧面级联耦合器对连续光纤激光器的影响

为了研究侧面级联耦合器对光纤激光器的影响,对自主研制的(1+1)×1侧面泵浦耦合器,以及某商品化的(2+1)×1耦合器进行了研究.实验中分别测试了2种耦合器的耦合效率,泵浦光传输损耗,以及信号光泄露等参数,然后用2种结构的耦合器分别搭建了光纤激光器.在耦合器为(1+1)×1结构的激光器中,注入975 nm泵浦功率444 W时,1 080 nm激光功率输出344 W,光-光转换效率77%;在耦合器为(2+1)×1结构的光纤激光器中,当975 nm泵浦功率注入444 W时,1 080 nm激光功率输出260 W,激光器的光-光转换效率59%.对比2种结构的激光器可以看出:对于目前商用的(2+1)×1耦合器来说,由于传输损耗比较大,很难实现级联结构,而实验室自主研制的侧面耦合器能够实现5个级联.

Effect of Cascaded Coupler on Continuous Fiber Laser

To analyze the influence of the side cascaded coupler on the fiber laser, the parameter of self-developed (1+1) × 1 cascaded couplers and commercial combiner of(2+1) × 1 was discussed. In the experiment, the coupling efficiency, translation loss of pump power, and the insertion loss of signal power were measured about the two couplers, and based on the two types of couplers, the study of all fiber lasers was carried out. In the fiber laser with the (1+1) × 1 coupler, 344 W of 1080 nm was obtained with the 975 nm pump power of 433. 8 W, and the optical to optical conversion efficiency was 77%. In the fiber laser with the (2+1) × 1 coupler, when the pump power of 975 nm was 433. 8 W, the output power of 1080 nm was 260 W with the optical to optical efficiency of 60%. Comparison of two types of fiber lasers show that for the (2+1) × 1 coupler, it is difficult to realize the cascaded structure due to the large transmission loss. However, the ( 1 +1 ) × 1 side coupler can achieve 5 cascaded structure with small transmission loss.