大功率半导体激光器的远场分布特性

对于以TM模工作的大功率半导体激光器，利用矢量瑞利衍射积分公式，推导了描述其光波传播特性的非傍轴矢量场模型，数值计算了大功率半导体激光器光束的远场光强分布和发散角特性，并与标量非傍轴理论进行了比较．结论表明， 大功率半导体激光器的矢量光场和标量光场的光强分布和远场发散角都有一定差异，光强误差随光波的传输距离的增加而减小，随着垂直于结平面方向坐标的增大，误差也增大; 发散角误差与波导结构参数有关．

Analysis of far-field properties for a high-power laser diode

To design an optical system for high power laser diodes, its far field distribution should be acquired exactly. Using the vector Rayleigh-Sommerfeld far-field diffraction integral formula, a vector model for describing the propagation of a high-power laser diode is proposed. Through the analysis of the properties of the TM-mode propagation, the expressions for the optical intensity and divergence angle are deduced, and the error is also analyzed compared with the scalar theory. It is found that the far-field intensity distribution and the divergence angle between the vector and scalar model are different. The error of intensity distribution is proportional to the coordinate perpendicular to the junction plane and inversely proportional to the propagation distance, and the difference of the divergence angle is related to the constants of the waveguide structure.