提出了全光纤结构的光纤环被动锁相相干合成方案,在自制的光纤放大器基础上,实现了四路光纤激光的全光纤被动锁相相干合成。对合成的开环闭环功率、光谱、远场光斑图样、系统锁相带宽等特性进行了研究。系统开环时,输出功率在71~271mW之间起伏,系统闭环后,输出功率稳定在412mW左右,较开环平均功率提高了2.1倍,说明该方案能够实现有效的相位锁定。系统锁相带宽大于50kHz,具有较好的稳定锁相能力。通过提高各路光纤放大器的功率和采用承受功率更高的合束器,有望获得更高功率的相干合成输出。 A scheme of passive phase-locked fiber ring synthesis with all-fiber structure was proposed. On the basis of self-made fiber amplifier, all-fiber passive phase-locked synthesis of four fiber lasers was realized. The open-loop closed-loop power, spectrum, far-field spot pattern and system phase-locked bandwidth were studied. When the system is open-loop, the output power fluctuates between 71 ~ 271mW. After the system is closed, the output power is stable at about 412mW, which is 2.1 times higher than the average power of the open loop. This shows that the scheme can achieve effective phase lock. System phase-locked bandwidth greater than 50kHz, with good stability and phase-locked capability. By increasing the power of each fiber amplifier and using the combiner with higher power, it is expected to achieve higher power coherent composite output.