研制了一种基于管状预电离的可调谐横向激励大气压(TEA)CO₂ 激光器。激光器采用光桥结构和折叠腔技术,输出稳定、结构紧凑。采用光栅谐振腔,实现了激光的调谐输出。激光器可输出谱线73条,波长范围为9.19-10.86 μm,其中45条谱线输出能量大于2 J。对于P10(20),R10(20),P9(20),R9(20)四条谱线,获得最大的激光脉冲能量分别为5.3,5.4,5.5,5.1 J,对应的电光转换效率分别为9.6%,9.8%,10.0%,9.3%;获得的最高电光转换效率依次为10.3%,10.7%,10.7%,10.7%。在气压为30 kPa下,激光器获得的最大比注入能量为2.626 J/(L·kPa),P9(20)谱线获得的最大比输出能量为0.205 J/(L·kPa)。测量了不同气压下的四条谱线的激光脉冲波形,输出的激光脉冲宽度值有所不同,其中R9(20)的脉冲宽度最大。测量了光束远场发散角,其值为2.6 mrad。实现了激光器的高重复频率可调谐输出,重复频率最高可达190 Hz。

A tunable TEA CO₂ laser with tubulous preionizer is developed.With optical bridge and folded cavity,laser is compact and stable.Tunable laser output is realized by grating resonator.73 lines of the CO₂ molecule rotational transition which wavelengths range from 9.19 to 10.86 μm are obtained,and there are 45 lines whose pulse energies of laser radiation exceed 2 J.The maximum pulse energies of P10(20),R10(20),P9(20),R9(20) are 5.3,5.4,5.5 and 5.1 J with the corresponding electro-optical efficiency of 9.6%,9.8%,10.0%,9.3%;The maximal electro-optical efficiency of the above four lines are 10.3%,10.7%,10.7% and 10.7% respectively.Under the gas pressure of 30 kPa,the maximal specific injection energy is 2.626 J/(L·kPa),and the maximal specific output energy of P9(20) is 0.205 J/(L·kPa).Laser pulse waveforms of the above four lines with different gas pressures are measured;The output pulse widths vary from each other,and the width of R9(20) is the largest.The far-field divergence angle is 2.6 mrad.Tunable high repetition laser output is realized at the repetition rate of 190 Hz.