本文设计了一种紧凑型端面泵浦电光调Q Nd∶YAG激光器。为实现激光器整体结构紧凑, 以快轴准直后的半导体激光器叠阵(Laser Diode Arrays,LDAs)作为泵浦源。使用焦距分别为40 mm和25 mm的球面镜和柱面镜将泵浦光耦合至Nd∶YAG晶体内。利用Tracepro软件模拟了晶体入射端面和出射端面的光场分布。在采用Ф6 mm×30 mm、掺杂浓度10at.%Nd∶YAG晶体作为增益介质时, 入射与出射泵浦光斑分别为5 mm(慢轴)×45 mm(快轴)和3 mm(慢轴)×6 mm(快轴), 吸收效率为83%。利用Ansys软件模拟了在22 ℃和60 ℃条件下Nd∶YAG激光器壳体在360 s内的温度场动态分布。实验结果表明, 本文设计的紧凑型激光器可以实现稳定的脉冲激光输出。在重复频率分别为30 Hz和50 Hz条件下, 获得了单脉冲能量为30 mJ和25 mJ的单脉冲输出, 对应脉冲宽度分别为18 ns和16 ns, 斜效率分别为116%和1471%。实验结果表明, 本文设计的紧凑型激光器可以实现稳定的脉冲激光输出。

A compact end-pumped Electro-optical Q-switched Nd∶YAG laser was designed in this paper. In order to achieve compact construction, laser diode arrays(LDAs) with collimated fast axes were used as pumping source. A spherical lens with a focal length of 40 mm and a cylinder lens with focal length of 25 mm were used as a group for the coupling lens. The LDAs′ beam profiles on the incident and exit faces were calculated using Tracepro software. The simulation results indicate that when taking a Φ6 mm×30 mm Nd∶YAG with a doping concentration of 10at.% as the gain medium, the spots on the incident and exit faces were 5 mm(slow-axis)×45 mm(fast-axis) and 3 mm(slow-axis)×6 mm(fast-axis), respectively, and the absorption pumping power was about 83%. Dynamic temperature field distributions of Nd∶YAG larer in 360 s at 22 ℃ and 60 ℃ were simulated by Ansys software. Output pulsed energy of 30 mJ and 25 mJ were achieved while the repetition frequencies were 30 Hz and 50 Hz, corresponding to a slope efficiency of 116% and 1471%. The pulse durations were 18 ns and 16 ns, respectively. The experimental results show that the designed compact laser in this paper can achieve stable pulse laser output.