CO_2激光器支线相干性动态再建过程的实验观察

Observation on the Reconstructing Process of CO_2 Laser Branch Line Coherence

采用外场目标对腔内调频连续波进行时间延迟 ,并用相干探测方式获取信号。分析表明动态谐振腔连续波CO2 激光器支线起振的典型时间为 2 0 μs,支线竞争结束并不意味着起振的支线相干性同时达到最佳状态。实验观察到相干性建立所需的最短时间比支线起振延迟 6 μs,且大多数支线相干性的建立需要更长时间。

The reconstructing process of the branch lines of a continuous wave CO2 laser was observed experimentally with the help of a FMCW laser radar system. It was considered that the branch line was stabilized when the heterodyne signal of a far-field target appears. It is concluded that different branch line takes different time to reach its stability, and the typical time is about 20 μm. Especially, the end of the competition between branch lines does not mean the coherence has reached its best situation. The observation shows that it takes at least 6 μm to reconstruct the coherence of a branch line.