时间分辨的脉冲氙灯光谱测试与分析

Testing and Analysis of Time Resolved Pulse Xenon Lamp Spectrum

高功率激光装置中的片状放大器普遍采用高功率脉冲氙灯作为抽运源,氙灯的辐射光谱与片状放大器的增益性能密切相关。基于暗室中搭建的时间分辨率为2μs的氙灯光谱测试系统,测试氙灯在不同放电时刻的辐射光谱。结果表明:相同电流密度对应的上升沿、下降沿时刻的氙灯辐射光谱存在显著差别,上升沿光谱的分立谱明显;当电流密度为0.866kA·cm^(-2)时,如果不施加预电离,上升沿的辐射光谱能量比下降沿低48%,施加预电离后这种差距缩小至24%;预电离可以有效提高上升沿时刻的光谱强度,是提高氙灯辐射效率的有效途径之一;对氙灯辐射光谱的原模型进行修正,可使其与测试光谱数据更吻合。

High power pulse xenon lamps are usually used as the pumping source for slab amplifiers in high power laser facilities. The spectrum of xenon lamps is strongly linked to the gain performance of slab amplifiers. A spectrum testing system in a dark room with the time resolution of 2 μs is built to test the xenon lamp spectra at different discharging time. The results show that the xenon lamp gives quite different spectra for rising and falling edges of the current waveform with the same current density. The rising edge spectrum has many obvious discrete spectra. If no pre-ionization is applied, the radiation spectrum energy at the rising edge is 48% lower than that at the failing edge when the current density is 0. 866 kA·cm^-2. If pre-ionization is applied, the difference reduces to 24%. The pre-ionization can effeetively increase the radiated energy of the rising edge, and the pre-ionization is an effective way to increase the radiation efficiency of the xenon lamp. The original xenon lamp radiation spectrum model is modified to agree with the experimental spectral data well.