Tunable Chirp-free Pulsed Injection of TEA CO₂ Laser Oscillators for Doppler Wind LIDAR Applications

Abstract

A frequency stable self-sustained low-pressure TE CO₂ laser oscillator incorporating an intracavity telescope has been developed with a variable pulse duration of between 30 and 10 μs. Heterodyne measurements show that the intrapulse frequency is constant to within 50 kHz for a 20 mJ output pulse for the first 8 μs of the optical pulse. The laser output has been used for pulsed injection into a dispersionless TEA CO₂ laser cavity to obtain single line, single mode selection and the results obtained are compared with those obtained from a c.w. injection source.