【作者】 贾伟；

【导师】 胡永明； 张小民；

【作者基本信息】 国防科学技术大学 ， 光学工程， 2005， 博士

【摘要】 大口径激光二极管阵列的高效泵浦耦合技术是高功率二极管泵浦固体激光系统急需解决的关键技术之一。它包括两方面的要求:将大口径激光二极管阵列输出的泵浦光高效缩束,从而在增益介质内实现较高的储能密度;改善泵浦光的空间分布,在增益介质内实现较均匀的储能分布。本论文针对适用于大口径激光二极管阵列的高效耦合技术进行了详细的研究。首先通过对近年来各种典型耦合方式的分析和对比发现,空心透镜导管耦合是目前最适用于大口径激光二极管阵列的耦合方式。利用自主开发的二极管阵列泵浦固体激光全三维模拟软件,对空心透镜导管进行了全面的研究,特别是各设计参数对耦合效果的影响,从而总结出空心透镜导管耦合系统的设计方法。按照这种方法设计的空心透镜导管耦合系统,能够在对大口径激光二极管阵列输出的泵浦光进行高效缩束的同时,实现良好的泵浦均匀性。在不考虑内壁反射损耗的情况下,即使将泵浦光束缩束100倍,也能够实现70%以上的输出效率,这是现有其他耦合方式难以实现的。作为高功率DPL的关键技术之一,大口径激光二极管阵列的高效耦合问题得到了很好的解决。将研究得出的空心透镜导管耦合系统及其设计方法应用于10J级二极管泵浦重复频率固体激光系统的设计中。设计了16kW和48kW端面泵浦片状放大器,将两种阵列输出的平均发光强度不足0.5kW/cm~2的泵浦光分别缩束36倍和27倍。激光介质有效区域内的泵浦强度全面超过10kW/cm~2,调制度小于1.2。激光介质内的有效储能及其均匀性都达到了系统设计要求。简要分析了10J级重复频率DPSSL的系统结构,并利用神光99软件对系统光传输进行模拟,确定了片放级多程放大结构。在充分考虑系统损耗的情况下,模拟得到了系统输出能量和光斑的空间分布。系统片放级光光效率超过15%,与美国利弗莫尔实验室的Mercury系统基本相当。更多还原

【Abstract】 High-efficient coupling technology is the key technology of the high power diode-pumped solid state laser systems. It includes the requests of two respects: condense the pump radiation of large-scale diode arrays efficiently, thus in gain medium realize the high density of energy storage; improve space distribution of the pump radiation, realize perfect pumping-uniformity in the gain medium. This thesis had carried on detailed research to the high-efficient coupling technology suitable for the large-scale diode arrays.Found with the contrast through an analysis of various kinds of coupling ways in recent years at first, hollow lensduct coupling was the most suitable way for the large-scale diode arrays at present. Utilize the three-dimensional DPSSL simulation software of independent development, an overall research of the hollow lensduct had been carried on; especially the impact on coupling result of every parameter, thus the design method of the hollow lensduct coupling system was summarized. Hollow lensduct coupling system, which designed according to the method, could condense the pump radiation efficiently with perfect pumping-uniformity. In the situation that the reflection loss of the duct inwall was not in considering, even condensed the pump beam 100 times, it could realize the output efficiency of more than 70%, this was that the other coupling way hardly to accomplish. As one of the key technology of high power DPSSL, the high-efficient coupling problem of the large-scale diode arrays got a very good settlement.The hollow lensduct coupling system was applied to the design of 10J diode pump repeated frequency solid state laser system. 16kW and 48kW end-pump disk amplifier were designed, they condensed the pump radiation of the two diode arrays of 36 times and 27 times separately, which average radiant intensity were lower than 0.5kW/cm~2. The pump intensity on the effective area of the gain medium exceed 10kW/cm~2 with a modulate degree of below 1.2. The effective energy storage and uniformity in the gain medium had all reached the systematic designing requirement. The system scheme of 10J repeats frequency DPSSL system was briefly analyzed, and the transmission of the laser in the system was simulated by SG-99 software. The multi-pass scheme of the disk amplifiers was confirmed. In the situation that the system losses were fully considered, the energy and space distribution of the system output was provided. The optic-to-optic efficiency of the multi-pass disk amplifier system exceeds 15%, which was at the same level with the Mercury system of Lawrence Livermore更多还原