激光表面改性3kW半导体激光器矩形光斑聚焦系统研究  

Research on Focusing System of Rectangular Spot for 3 kW Diode Laser Used in Surface Modification

作　　者：许成文[1] 钟理京 秦应雄[1] 郭海平[1] 唐霞辉[1] 

机构地区：[1]华中科技大学光学与电子信息学院激光加工国家工程研究中心,湖北武汉430074

出　　处：《中国激光》2016年第1期1-9,共9页Chinese Journal of Lasers

摘　　要：针对3 kW 半导体激光器应用于机器人表面改性系统，聚焦光斑不均匀问题，提出了一种采用菲涅耳透镜对面阵高功率半导体激光器输出光斑进行聚焦匀化的方法，设计出尺寸为10 mm×2 mm 的均匀矩形光斑。利用Zemax 和Matlab 软件进行仿真分析，研究了菲涅耳透镜楞距和入射光发散角对聚焦系统焦斑均匀性的影响。结果表明，当菲涅耳透镜楞距在1 mm 以内时，焦斑均匀性最佳约为94.90%。随着楞距的继续增大，输出光斑均匀性会逐渐降低。当楞距增大到2.5 mm 后，光斑的均匀性不再随楞距的增大而变化，基本稳定在93.85%左右。焦斑的均匀性会随着发散角的增大有所提高，但是发散角太大会使聚焦难度增加，而且光斑均匀性也随之劣化。当菲涅耳透镜楞距为1 mm，入射光发散角在12.5~20 mrad范围内时，焦斑均匀性最好约为95.22%。For 3 kW diode laser used in robot surface modification system, the focal spot is uneven. A kind of focus and homogenization method by using the Fresnel lens for the focusing system of high power diode laser has been put forward, and a uniform rectangular spot of 10 mm×2 mm has been designed. Through the simulation analysis of Zemax and Matlab, the influences of the pitch of Fresnel lens and the divergence angle of incident rays on the homogeneity of the focal spot have been studied. The results show that the best uniformity of the focal spot is about 94.90% when the pitch of Fresnel lens is less than 1mm and the uniformity gets worse and worse with the increase of the pitch of Fresnel lens. As the pitch increases to 2.5 mm, it has less influence on the uniformity of the focal spot, and the uniformity basically stables at around 93.85%. Meanwhile, the uniformity will be improved with the increase of divergence angle, but large divergence angle will increase the difficulty of focusing and make the uniformity get worse and worse. When the pitch of Fresnel lens is 1mm and the divergent angle is from 12.5 mrad to 20 mrad, the best uniformity of the focal spot is 95.22%.

关 键 词：激光器 半导体激光器 菲涅耳透镜 表面改性 矩形光斑 

分 类 号：TN248.4[电子电信—物理电子学]