基于透射式非稳腔的单纵模TEA CO_2激光器

为了获得TEA CO_2激光器高质量的单纵模输出,对种子注入锁定的TEA CO_2激光器进行了研究。首先,本文提出了一种透射耦合输出的虚共焦非稳谐振腔方案,利用Glad软件的Prony法对腔模的演化进行了仿真分析,并实验记录了近场与远场的光斑光强分布。仿真结果与实验结果吻合,验证了此腔型方案的合理性。其次,在此腔型的基础上进行了腔外种子注入锁定实验,实验结果显示:自由振荡时存在频率为195 MHz的拍信号,当种子注入锁定成功后,输出激光拍频消失,波形变光滑,峰值功率降低48.6%,脉冲产生时间缩短20ns。实验结果与已有成果吻合,验证了此种透射式非稳腔的TEA CO_2激光器具有输出高质量单纵模的能力。

Single longitudinal mode TEA CO2 laser based on transmissive unstable resonator

In order to obtain a high-quality single-longitudinal-mode output from a TEA CO₂ laser, a study on a TEA CO₂ laser with seed injection locking is carried out. A virtual confocal resonator with transmission coupling is proposed. The evolution of the cavity mode is simulated by Prony's method of the Glad software. The near-field and far-field intensity distributions are recorded experimentally. The results demonstrate that the simulation results are in good agreement with the experimental results, which verifies the rationality of the cavity scheme. On the basis of this resonator, the experiment of seed injection locking is carried out. The experimental results show that there is a beat signal with a frequency of 195 MHz when the oscillation of unstable resonator is free. When the seed injection is successfully locked, the output laser beat disappears, the waveform becomes smooth, the peak power is reduced by 48.6%, and the pulse generation time is shortened by 20 ns. The experimental results agree well with the existing results, which verifies that the TEA CO₂ laser with such a transmissive unstable resonator has the ability to output a high-quality single longitudinal mode.