为了满足308 nm准分子激光皮肤治疗仪对激光输出参数, 特别是激光能量稳定性的要求, 首先建立了激光能量衰减模型, 提出了基于激励电压补偿能量的比例积分(PI)算法, 对PI算法进行了理论分析、模拟实现; 其次对准分子激光器进行了实验研究, 设计了高压激励电源和基于快速光电二极管的激光能量无损检测模块, 实验研究了激励电压与输出能量的关系、激光器能量衰减特性以及引入PI算法后的激光器能量稳定特性; 结果表明: 激励电源和能量检测模块满足PI算法的调节精度和响应速度, 引入PI算法后, 准分子激光器输出能量在1千万个脉冲内仍能维持目标能量17.5 mJ附近, 能量方差从0.2%缓慢上升至3%, 满足准分子激光皮肤治疗仪的使用需求。

In order to meet output parameters, especially the stability of the laser energy requirements for the 308 nm skin therapeutic apparatus, first of all, the laser energy attenuation model and proportional integral (PI) algorithm based on energy compensation by the excitation voltage were established, its theoretical analysis and simulation were compeleted. Secondly, the experimental research on excimer laser was carried out which included high voltage excitation power supply and laser energy detection module based on fast nondestructive photoelectric diode. Meanwhile, the experimental research on the relationship between excitation voltage and output power, characteristics of laser energy attenuation and laser energy stability properties with the introduction of PI algorithm was studied. The results show that the power supply and energy detection module meet the PI algorithm control precision and response speed. Meanwhile, the excimer laser output energy can still maintain a target energy within 17.5 mJ and energy variance is slowly rising from 0.2% to 3% in the 10 million pulses after introducing the PI algorithm, which well meets the usage requirements of excimer laser skin therapeutic apparatus.