Similarity criteria in calculations of the energy characteristics of a cw oxygen – iodine laser

The calculated and experimental data on the energy efficiency of a cw oxygen – iodine laser (OIL) are analysed based on two similarity criteria, namely, on the ratio of the residence time of the gas mixture in the resonator to the characteristic time of extraction of the energy stored in singlet oxygen td and on the gain-to-loss ratio Π. It is shown that the simplified two-level laser model satisfactorily predicts the output characteristics of OILs with a stable resonator at τ_d ≤ 7. Efficient energy extraction from the OIL active medium is achieved in the case of τ_d = 5 – 7, Π = 4 – 8.