摘要
激光二极管抽运的全固态激光器具有体积小、质量轻、效率高的特点,是目前星载激光雷达系统的主要发射光源。介绍了一种基于传导冷却的LD阵列侧面抽运Nd:YAG晶体的Zig-Zag板条激光器。板条介质能够消除棒状介质带来的一阶热聚焦和应力退偏效应。采用55个准连续激光二极管沿板条晶体长度方向均匀排列,通过柱面镜耦合进行均匀抽运。Nd:YAG晶体的散热是采用与其热膨胀系数匹配的金属热沉由光泵背面将热量传导出去。LD阵列的散热是通过紫铜热沉传导到底板,再由热管传递出去。实验中使用平凹激光谐振腔,重复频率20Hz,获得单脉冲能量大于150mJ的激光输出,脉冲宽度10ns左右,光-光转换效率大于15%。实验表明:该激光器具有在太空中应用的潜力。
Diode-pumped solid-state lasers are currently main optical source of space-based lidar system, because of its small volume, light weight and high efficiency. A conductively cooled diode arrays side-pumping Nd：YAG Zig-Zag slab laser was introduced. The slab geometry medium could eliminate the first order thermal lensing and depolarization effects of stress of rod geometry medium. 55 quasi-cw diode bars were placed symmetrically along the length direction of slab＇s crystal, and coupled through a cylindrical lens, uniformly pumping. Thermal conduction of Nd：YAG crystal was done on the reverse pumping face by metal cooling heat sink. The heat dissipation of diodes arrays was conducted to bottom through heat sink, transmitted out by heat pipes. A plane-concave rear mirror and a fiat output coupler were used as laser resonator. The pulses had been obtained with energy of 150 mJ, repetition frequency of 20 Hz, pulse width of 10 ns. The optical to optical conversion efficiency was more than 15%. Experiment results show that this laser is capable of use in space.
出处
《红外与激光工程》
EI
CSCD
北大核心
2009年第3期448-451,共4页
Infrared and Laser Engineering
基金
国防科技预研基金项目
