激光诱导等离子体开关控制脉宽实验研究

 利用激光诱导等离子体开关技术，在1 064 nm的Nd：YAG固体激光器上获得了脉宽4.4~6.4 ns的短脉冲激光输出。激光电离空气产生的等离子体开关控制脉冲宽度时，聚焦透镜焦距越短，压缩后的脉宽越窄，但激光能量损耗越大。压缩后的激光脉宽与激光能量近似成双曲线关系。在控制脉宽光路的焦点处放置带孔的Cu薄片可抑制等离子体的扩散，得到了脉宽最短可达4.4 ns的激光输出。

Pulse duration control by laser induced plasma switch

Based on laser induced plasma switch technology,the output pulse width of 4.4 ns of the solid-state Nd:YAG laser is obtained.The influences of the focal length of the lens and the laser beam energy on the shortened laser pulse width are presented.The shorter the focal length is, the narrower the shortened pulse durationis,the greater the laser energy loss is.A hyperbola relationship between the pulse duration and the laser pulse energy is obtained.The laser pulse width is shortened to 6.4 ns by the plasma switch generated by the laser discharge in atmosphere.Placing a Cu pinhole on the focus of the lens to prevent the plasma from diffusing,a short output pulse with a width of 4.4 ns is obtained.