圆柱透镜对半导体激光光束准直性能的改进

根据光线传输的基本原理，通过计算和推导，用解析式表达并讨论了半导体激光器快轴方向发散光束通过圆柱透镜后的准直特性、光强分布和光能转换效率与圆柱透镜的半径、介质折射率、介质损耗、安装距离等可调参数以及界面反射的关系。说明了安装位置直接影响到准直效果；透镜半径、折射率和介质损耗不仅影响到准直后光斑的大小、光强分布和光能转换效率，而且影响到偏振状态的重新分布，因此，要获得最佳准直效果必须略微离焦安装；还需根据具体使用要求综合考虑各参数对光斑大小、光强分布和光能转换效率的影响，以采用适当的参数，并考虑是否进行增透处理。为正确认识和使用微圆柱透镜改善半导体激光快轴方向光束的发散，提高光束质量提供了理论依据。

Improving on the Collimating Performance of Cylindrical Lens to the Beam of Laser Diode Bar

According to the basic principle of light ray propagation, the collimating characteristic, the intensity distribution, the transfer efficiency of light energy and the transport coefficient for the laser diode ray in the fast axis direction passing through a cylindrical lens are analytically calculated and discussed. Based on analyzing a few of adjustable parameters, such as the radius of cylindrical lens, media index, media loss, lens location, and interface reflection, some conclusions are deduced that the location of cylindric lens directly influence the collimating effect of diode rays; lens radius, media index, and media loss not only influence spot size, intensity distribution, and energy transport, but also newly polarization distribution. That is to say, the cylindrical lens must be set out of focus slightly and the every parameter including the optical coating of transform system must be optimized. Above consequences are usefull to design a collimating system with micro cylindrical lens that can considerably decrease the diverging angle of laser diode in fast axis and improve beam quality.