可低温工作的窄脉冲宽温激光器

Narrow Pulse Width lasers Operating over Wide Range of Low Temperature

报道了一种可在低温环境下和100℃以上的宽温范围内稳定工作的纳秒级被动调Q的Nd…YAG激光器。谐振腔采用抗失谐的双Porro棱镜组合腔型,以热电制冷器控温的垂直腔面发射激光器侧面抽运Nd…YAG板条晶体,被动调Q晶体为Cr^(4+)…YAG。在抽运峰值功率为1kW,重复频率为1Hz的条件下,测量了激光器在不同温度下的工作情况。结果表明在-75～40℃温度范围内,激光输出平均能量为18.79mJ,标准差为2.29mJ,脉宽约为4ns,近场光斑直径约为5mm,远场发散角小于0.9mrad。激光器体积小、结构紧凑、可靠性高,十分适合宽温范围尤其是低温环境下的空间激光应用。

In this study,we describe a passively Q-switched Nd…YAG nanosecond laser capable of operating stably over 100 ℃ and at low temperatures.The resonator is based on a stable,double-Porro-prism cavity structure.A Nd…YAG slab is side-pumped via a vertical-cavity,surface-emitting laser array,and the temperature is controlled by a thermoelectric cooler.The passively Q-switched crystal is Cr4+…YAG.We have tested the performance of the laser at different temperatures with a 1 kW peak pump power and 1 Hz repetition frequency.The results show that the average output energy of the laser is 18.79 mJ,the standard deviation is 2.29 mJ,the pulse width is^4 ns,the near-field spot diameter is^5 mm,and the far-field divergence angle is less than 0.9 mrad in the temperature range of-75-40℃.The lasers has a small size,compact structure,and high reliability.It is thus suitable for space-laser applications under a wide range of low-temperature conditions.