为了研究提高无极灯光效的方法,本文测量了无极灯启动阶段的电参数和发射光谱,分析了点灯后阻抗、Hg原子光谱强度、Ar原子光谱强度、等离子体参数和放电模式随时间的变化规律。结果表明,在启动阶段,无极灯阻抗发生了升-降-升的变化;Hg原子谱线强度在某稳定位置附近做相对稳定的波动;Ar原子光谱强度迅速下降到某稳定值;电子浓度迅速下降到某稳定值,中能电子温度相对稳定;放电处于H型放电模式。这为进一步设计电子整流器和提高无极灯的光效奠定了基础。
The starting characteristics of the electrodeless lamps,such as the changes in lamp impedance,emission intensity of mercury and argon atoms,time evolution of the plasma parameters,and discharge mode after lamp ignition,were experimentally studied.The results show that the impedance of the lamp in the starting stage,first increases rapidly for a couple of seconds,then decreases less rapidly,and finally,increases slowly.We found that the Hg emission intensity fluctuates around a stable value;whereas Ar emission intensity rapidly drops to a constant.The electron density decreases,stabilizing somewhere;and the temperature of the middle energy electrons is fairly stable.We propose that the plasma may discharge in H-mode.Possible mechanism(s) was also tentatively discussed.