为提高靶面光强，高功率激光驱动装置中常采用多路激光组束打靶，目前主要采用2×2集束的方式。集束聚焦系统中使用的透镜可分为离轴透镜和非离轴透镜,采用非离轴楔形透镜的集束聚焦系统在理想条件下可获得很好的焦斑质量。建立了2×2集束聚焦系统的光传输模型，并仿真研究了实际安装调试过程中各种误差对其焦斑造成的影响。结果表明，反射镜角度和透镜平移对系统的焦斑质量影响很大，需要对其进行精密调试；透镜安装角度和焦距误差对系统的焦斑质量影响较小，现有条件比较容易满足。本文研究可提高研究人员对多光束相干合成集束方案的认识，对实际系统的安装调试有一定指导意义。

Large aperture high-power laser drivers usually focus the high power laser beams in 2×2 quads to the target chamber center in order to increase the light intensity on the target plane. The large aperture wedged focus lenses are the core components in the focus system of quadruplets of beams, and it is thought possible to use four two-dimensional off-axis wedged focus lenses as four sub-lenses to make up a larger aperture wedged focus lens in form to focus the four beams. Given that the large aperture two-dimensional off-axis wedged focus lenses are processed and used difficultly, the wedged focus lenses are divided into three categories: the two-dimensional off-axis wedged focus lenses, the onedimensional off-axis wedged focus lenses, and the non-off-axis wedged focus lenses. On the basis of the three modes of the wedged focus lenses and the corresponding specific incidence angles of each sub-beam, the three focus schemes for the 2×2 beam array are put forward to comparatively research the light intensity distribution on the target plane. Research results show that from a perspective of the coherence among the four sub-beams, the phase factors of each sub-beam respectively introducing by the three focus systems with the two-dimensional off-axis, one-dimensional off-axis, and non-off-axis wedged focus lenses are asymmetric, asymmetric and symmetric inside each sub-beam, and symmetric, asymmetric and symmetric among the four sub-beams. Therefore, the wave front consistency of the four sub-beams decreases in the order of the focus systems with the non-off-axis, two-dimensional off-axis, and one-dimensional off-axis wedged focus lenses. The focus schemes with the non-off-axis wedged focus lenses for 2×2 beam array can get the narrowest main-lobe, the strongest peak-value intensity, the highest energy concentration ratio on the target plane, followed by the one-dimensional off-axis and two-dimensional off-axis wedged focus lenses. The off-axis mode of the wedged focus lenses not only increases the complexity in the course of processing and using, but also increases the main-lobe size, decreases the peak-value intensity and the energy concentration ratio, which obtains a weaker focusing characteristics than that of the non-off-axis mode of the wedged focus lenses. Research results can provide an important reference for the design of the focus system in the target area of high-power laser drivers.

The wedge-shaped lens is the key and special optical component of the final optics assembly (FOA) in high power laser facility. The wedge-shaped lens wedge angle measurement plays a remarkable role in focusing performance of high power laser. If processing angle and work attitude of the wedge-shaped lens deviate from the specific work angle, big surface deviation will be introduced into the FOA. Special shape of the wedge-shaped lens is not conducive to the measurements of the transmission profile and wedge angle. A set of wedge-shaped lens measurement adjustment programmes is proposed, including measurement of the wedge-shaped lens in processing process, and off-line measurement of wedge-shaped lens during alignment and on-line measurement during the debugging process. The scheme can ensure the processing precision and working attitude of the wedge-shaped lens, guarantee the beam quality and the positioning accuracy of the FOA components of high power laser system.

楔形透镜是高功率激光系统终端光学组件的关键元件，也是较为特殊的光学元件，楔形透镜的楔角测量关系着高功率激光的聚焦性能。终端组件中楔形透镜的加工角度、工作姿态一旦偏离了特定的工作角度，终端组件会引入大的面形偏差，楔形透镜特殊的形状不利于楔形透镜面形、楔角的测量。提出了一整套楔形透镜测量调整方案，包括楔形透镜加工过程中的测量方案，楔形透镜安装过程中的离线测量与调整方案，以及终端组件上线调试过程中的在线调试测量方案。该套方案的实施能够保证楔形透镜的加工精度，及组件中楔形透镜能够工作在最佳工作姿态，保障了高功率激光系统终端组件的光束质量和定位精度。

根据半导体激光器和单模光纤模场分布特点，用模式耦合理论研究了单模光纤与半导体激光器的耦合，结果表明将光纤端面制作成楔形微透镜可以使光纤与半导体激光器的耦合满足模场匹配和相位匹配的要求。用遗传算法对楔形光纤微透镜参数进行优化，得到楔角为88°，柱透镜半径为3.44 μm，耦合距离为6.13 μm时耦合效率达到最佳值，用Zemax光学仿真软件对耦合模型进行仿真，得到耦合效率为88.9%，耦合好的模块经激光点焊及高低温环境测试后，得到最大耦合效率为81.36%。实验结果与仿真结果相差不大，耦合输出功率满足了作为光纤激光器种子源的功率要求。