A HIGH-POWER Q-SWITCHED CO2-LASER USING INTENSE PULSED RF DISCHARGE EXCITATION

A compact high-power Q-switched CO2 laser has been developed using a c ombination of intense pulsed rf (13.56 MHz) discharge excitation and a high-speed rotating Q-switch chopper. Performance characteristics hav e been investigated as functions of Q-switching velocity, input discha rge energy density and laser gas composition. A pulse peak power of 30 0 kW and an average power of 740 W at 10 kHz pulse repetition frequenc y have been obtained simultaneously for a Q-switched laser based on a CO2 laser with 1.1 kW average power. By decreasing the repetition freq uency to 4 kHz, the peak power was enhanced to above 500 kW. An analyt ical model describing the unique features of the Q-switched CO2 laser has also been developed for quantitative evaluation of the laser perfo rmance. Good agreement was obtained between the theoretical model and experimental results.