1J高光束质量免水冷脉冲Nd∶YAG激光器

High Beam Quality Water-free Pulsed Nd∶YAG Laser with Output Energy 1 J

研制了一种TEC制冷LD侧泵高能量、高光束质量、电光调Q全固态Nd∶YAG激光器。在主振荡器中晶体棒的尺寸为φ7 mm×100 mm,Nd原子数比例为1.1%,LD泵浦的最大峰值功率为15 kW,在重复频率为10 Hz时,获得了350 mJ输出能量,脉冲宽度为9.7 ns,光束质量因子M 2在水平和垂直方向分别为3.3和3.8。使用主振荡功率放大结构,提高了最终的输出功率。第一级放大器Nd∶YAG晶体棒尺寸为φ7.5 mm×134 mm,在输出重复频率10 Hz、泵浦电流80 A、泵浦脉冲宽度200μs时,得到最大单脉冲能量700 mJ,脉冲宽度10 ns。第二级放大器Nd∶YAG晶体棒尺寸为φ8 mm×100 mm,泵浦电流为80 A。最终我们获得了最大的单脉冲能量1085 mJ,脉冲宽度10 ns,能量不稳定度小于3%,测量的光束质量因子M 2在水平和垂直方向分别为3.9和4.8,实现了焦耳级高光束质量Nd∶YAG激光器的小型化、无水冷化。

A LD side-pumped high-energy,high-beam-quality,electro-optic Q-switched all-solid-state Nd∶YAG laser with thermoelectric cooler is developed.The size of the crystal in the oscillator isφ7 mm×100 mm and the Nd atomic ratio is 1.1%.The maximum peak power of pumping LDs is 15 kW.At the repetition rate of 10 Hz,the oscillation output with the maximum pulse energy of 350 mJ is obtained with the pulse width of 9.7 ns,the beam quality M 2 of horizontal and vertical directions is 3.3 and 3.8,respectively.The MOPA structure is used to improve the final output power.The dimension of the Nd∶YAG crystal in the first amplifier isφ7.5 mm×134 mm,when the pumping current is 80 A and the width of pumping pulse is 200μs.A 700 mJ,10 ns laser pulse is obtained with the repetition frequency 10 Hz.The dimension of the Nd∶YAG crystal in the second amplifier isφ8 mm×100 mm and the pumping current is 80 A.The maximum output pulse energy is up to 1085 mJ with the pulse width of 10 ns.The energy instability is less than 3%,the beam quality M 2 of the horizontal and vertical directions is 3.9 and 4.8,respectively.The miniaturization and water-free of high beam quality Nd∶YAG laser at Joule level are realized.