Excitation of CO2 TEA lasers with self-sustained discharges

Problems are discussed regarding the optimization for the output energy of the total pressure and gas mixture composition of the CO2 laser with self-sustained volume discharge. It is shown that the ratio of the discharge electric field intensity to the neutral gas density depends only on the fraction of He in the gas mixture, that typical values of the average electron energy are 1.5 eV for conventional CO2 + N2 + He mixture and 1.8 eV for CO2 + He mixture, and that the efficiency of excitation of CO2 and N2 vibrational levels for all practical purposes does not depend on the fraction of He in the mixture if the latter does not exceed 95%. Results are presented of measurements of the output energy in CO2 lasers with conventional and double discharge systems and the efficiency of the contribution into the discharge made by the energy stored in the discharge capacitance is discussed.