基于外腔谱组束模型，详细分析了影响外腔谱组束耦合效率和光束质量的因素。结果表明：在存在Y偏移的情况下，耦合效率随光斑半径的增大而增加；在组束阵元数增加的情况下，优化组束阵列的耦合效率明显提高；使用外腔谱组束，为提高耦合效率和光束质量，应尽量选择焦距较长的传输透镜以及光斑半径较大的激光器。

Based on the spectral beam combining model, the factors influencing coupling efficiency and beam quality in an external cavity were analyzed in detail. The analytical results show that the coupling efficiency increases with the beam waist diameters when the fiber laser array elements are arranged as a linear laser arrays with offset Y, and the coupling efficiency for the optimized arrays will increase evidently. This investigation further shows that the lens with long focus has to be used for spectral beam combining with the external cavity in order to increase the coupling efficiency and obtain higher beam quality.