报道了两路纳秒脉冲光纤激光的相干合成(CBC)实验。利用主振荡功率放大(MOPA)结构搭建两路全保偏光纤激光放大器,利用随机并行梯度下降(SPGD)算法对两路放大器进行相干合成,获得了重复频率10MHz、脉冲宽度10ns、平均功率50mW的脉冲激光输出。系统闭环时目标圆孔内能量提高了1.76倍,远场光斑条纹对比度提高了4.38倍。 The coherent synthesis (CBC) experiment of two nanosecond pulsed fiber lasers was reported. The two fully-insulated fiber laser amplifiers were built by the main oscillator power amplifier (MOPA) structure. The two amplifiers were coherently synthesized by the SPGD algorithm. The repetition frequency was 10MHz, the pulse width was 10ns, the average power was 50mW Pulsed laser output. When the system is closed, the energy in the target hole is increased by 1.76 times, and the contrast of the far-field spot fringes is increased by 4.38 times.