光谱合成技术是一种有效的突破单根光纤激光器输出极限, 得到更高亮度的激光输出的方法。介绍了一种外腔振荡式单路光源的光纤激光光谱合成方案, 相比于现行的主振荡功率放大(Master Oscillator Power-Amplifier, MOPA)式单路光源的单光栅合成方案, 具有结构紧凑、阵列规模扩展能力强的优点。对该方案进行建模, 分析了合成系统中不同波长的单路激光光源的位置关系, 并对系统中的光纤排布、转换透镜像差等因素对合成效果的影响进行了仿真计算。搭建实验系统进行了初步的实验验证, 与理论结果能够吻合。对下一代光谱合成系统的构建以及光学元件的选择具有重要的指导意义。

Spectral beam combining is an effective way to break through the power limitation of a monolithic fiber laser and achieve high brightness fiber laser output. A spectral beam combining scheme was presented that the single element was structured by external-cavity fiber oscillator. This scheme had more compact structure and was able to contain more elements, compared with the current MOPA structure element. A theoretical analysis was conducted about the relationship between the wavelength and position of each element, and a numerical simulation was carried out about the influence of aberrations in the transform lens on cavity loss and combining effects. An experimental system was built, and the experimental results agree well with the theoretical analysis. This work has important guiding significance for the building of next generation spectral beam combining system.