为研究光纤耦合激光器的输出远场特征，基于ZEMAX光学设计软件，模拟了基于单发光区激光器芯片的多种光纤耦合结构，分析了不同耦合结构的输出远场特征。模拟结果表明：单管耦合输出远场分布通常为中间亮、边缘暗的圆形光斑。当准直后的光束快慢轴光束尺寸基本一致时，远场输出光斑均匀性会得到极大改善；当存在光纤轴心角向误差(大于1°)时，远场输出光斑的均匀性会明显降低。多单管耦合时，单管之间的台阶高度若大于准直后的快轴光斑尺寸，则对应的远场输出为有暗区的同心圆环，单管的数量对应圆环的数量。为了提高输出远场分布的均匀度，应严格控制合束单管之间的台阶高度。

In order to study the output far field characteristics of optical fiber coupled laser diodes, several kinds of fiber coupling structures based on single emitting diode laser chip were simulated by ZEMAX optical design software, the analysis on the far field characteristics were conducted . The simulation results show that the far-field output distribution of a single emitter coupling structure is usually a circular spot with a brighter center and a weak light zone outside. When the size of the collimation beam in the fast axis and slow axis is approximately the same, the far field output uniformity improves greatly. When the angular error of optical fiber along the central axis is large(more than 1°), the uniformity of the output far field spot reduces significantly. For multi-chip fiber coupling, if the step height between single emitters is greater than the size of the collimated beam in the fast axis, the output far field distribution is ring-like with dark zone, and the number of the emitters is corresponding to the number of rings. In order to improve the uniformity of the output far field distribution, the step height between the single emitters must be strictly controlled.