被动调Q激光器的输出抖动一般较大,为了降低这一输出时间抖动,同时实现激光器的小型化,可以根据增益开关工作原理,利用电源控制抽运功率密度变化,实现被动调Q情况下的增益开关。根据这一原理研制了环形激光二极管(LD)抽运增益开关调Q激光器。这种新型被动调Q激光器的输出能量为30 mJ,输出脉冲宽度约16 ns。实验中将传统的两套抽运源减少为一套,通过控制电源波形直接形成抽运功率的增益台阶脉冲,减少了影响时间跳动的因素。多发次统计测量结果表明,激光脉冲与电源输出外触发信号的时间抖动小于1 μs。根据测量的抽运预脉冲功率稳定性和阶跃脉冲的瞬时抽运功率计算的输出抖动与实验结果基本相符。

Generally, a passive Q-switching laser has a wider time jitter. In order to reduce the jitter time and the size of the laser, gain switching principle is researched. According to the principle, the pumping power density is controled by the power which generates a step current. A Q-switched laser pumped with a ring laser diodes according to gain switching principle is developed. A 30 mJ output energy and about 16ns pulse duration of this kind of passive Q-switching laser are obtained. There is only one set of pupming source to be used in the experiment. Gain step pulse is directly obtained by controling the waveform of current, and the factors which affect the laser pulse jitter are reduced by this way. Statistic reports of multi-measurement indicate that the laser pulse jittering time is less than 1 μs comparing with the trigger signal. According to the measured stability of pre-pumping and the transient power of the step pulse, the jitter time Δτd is calculated, which agrees well with the experimental result.