固体开关小能量准分子激光器的设计与实验研究

Design and Experimental Study of an Excimer Laser Based on Solid State Pulsed Power Module

准分子器件重复频率高于千赫兹时,闸流管作为传统的放电开关由于寿命瓶颈而不能满足长期稳定工作的要求。采用固体开关结合磁脉冲压缩技术的固态脉冲功率模块(SSPPM)来替代闸流管进行高压快速放电,激光器可在高重复频率下长寿命运行。设计了无闸流管的固体开关小能量准分子激光器,其核心技术是基于SSPPM的应用,并采用金属-陶瓷结构腔体和电晕预电离以延长气体工作寿命。电极放电电压10～14 kV,电压上升时间约150 ns,抽运功率密度3.9～7.6 MW/cm^3。ArF运转时,获得最大单脉冲能量11 mJ激光输出,最高重复频率300 Hz。其输出指标可满足当前准分子眼科设备、光谱学研究等需要。

Thyratron-based excimer lasers are not available for some fields where high pulse repetition rate is desired. A thyratron-free alternative is to introduce solid state pulsed power module （SSPPM） which combines solidstate switch with magnetic switch and promises an infinite lifetime. A SSPPM-based ArF excimer with metal-ceramic configuration was designed. Corona pre-ionization was employed to achieve a homogeneous and clean pre-ionization. A 10- 14 kV pulse was generated by the SSPPM for electrodes discharge. The risetime of the pulse was about 150 ns. Under the pumping density of 7.6 MW/cm^3 the maximum laser output energy of 11 mJ was obtained at 193 nm. The maximum repetition rate was up to 300 Hz. This laser may satisfy the applications such as laser vision correction, dermatological treatment and spectroscopy.