Pure single line oscillation of HF lasers in fine atmospheric window.

The pure P₂(8) line radiation of chemical hydrogen fluoride (HF) laser which can be weakly absorbed by atmosphere was generated using an absorbed module in a line-selected cavity. A numerical model of laser gain was investigated to predict and optimize the laser performance. An experimental verification was carried out in a compact continue wave (cw) tunable chemical HF laser device. It is found that P₁(11) line can be suppressed by fundamental HF particles generated by combustion reaction, meanwhile the proportion of P₂(8) line can be increased close to 100% from original 38%. The absorbance as well as output power of P₂(8) line can also be influenced by concentration of absorbing media. [ABSTRACT FROM AUTHOR]