高功率650~660 nm波段激光器在可见光光电对抗领域具有重要作用，目前该波段光源由固体激光器通过半导体激光器泵浦并倍频输出，输出功率高、光束质量近衍射极限，但转换效率低。半导体激光器的转换效率高，但输出功率低，需要通过增加激光单元的方法提升功率，并通过激光合束的方式提升光束质量。文中提出外腔光谱合束的650 nm波段半导体激光器结构，通过实验验证可实现连续功率为7.3 W、光谱线宽为6.45 nm、电光转换效率为23.4%的650 nm波段激光输出，光束质量为M²_X=1.95，M²_Y=11.11，接近固体激光器，未来通过增加合束的激光单元数量并结合偏振合束可以获得更高功率的650 nm波段激光。

针对目前铜、金等金属材料加工的实际应用需求，开展了连续输出功率500 W的光纤耦合输出蓝光半导体激光加工光源研究。基于平面窗口TO封装的蓝光半导体激光单管器件，设计采用长后工作距的快轴准直镜和慢轴准直镜分别准直，获得低发散角、高光束质量的单元准直光束；结合二维空间合束、偏振合束和光纤耦合，将144个蓝光单管器件耦合进200 μm/NA 0.22光纤，通过ZEMAX软件对半导体激光光路进行光线追踪模拟；并从实验上实现，3 A电流驱动下，200 μm/NA 0.22光纤输出连续功率523 W，电光转换效率29 %。该激光光源具有直接加工铜、金等材料的能力。

With the rapid development of laser technology, laser as the light source of night vision illuminating can realize long-distance and clear imaging, which has been widely used in laser active illuminating field. A high-power diode laser with a wavelength of 808 nm was designed as the laser active illuminating source, and the output power of no less than 100 W was obtained by spatial beam multiplexing, polarization multiplexing, and high efficiency fiber coupling techniques. In view of the beam homogenization of illuminating source, a novel beam homogenization system based on waveguide is proposed in this work. A square spot with a horizontal divergence angle of 40°, a vertical divergence angle of 10°, and an illuminating power ratio of 4:1 was obtained by a collimating lens. Comparing with the traditional circular illuminating beam, the square illuminating beam can match the illuminating angle of CCD camera better, and the energy utilization rate is higher. In addition, by optimizing the structure of waveguide and collimating lens, the illuminating angle can be changed to meet the illuminating requirements under different conditions theoretically.

In this research, the highly efficient external cavity feedback technology based on volume Bragg grating (VBG) is studied. By using the structure of a fast axis collimating lens, the beam transformation system, a slow axis collimating lens, and VBG, the divergence angle of the fast and slow axes of the diode laser incident on the VBG is reduced effectively, and the feedback efficiency of the external cavity is improved. Combined with beam combining technology, fiber coupling technology, and precision temperature control technology, a high-power and narrow-linewidth diode laser pump source of kilowatt class is realized for alkali metal vapor laser pumping. The core diameter of the optical fiber is 1000 µm, the numerical aperture is 0.22, the output power from the fiber is 1013 W, the fiber coupling efficiency exceeds 89%, and the external cavity efficiency exceeds 91%. The central wavelength is 852.052 nm (in air), which is tunable from 851.956 nm to 852.152 nm, and the spectral linewidth is 0.167 nm. Research results can be used for cesium alkali metal vapor laser pumping.