Effects of Particulate Matter on Atmospheric Propagation of CO2 Laser Radiation.
Semi-annual rept. 1 Jul-31 Dec 72,
UNITED AIRCRAFT RESEARCH LABS EAST HARTFORD CONN
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The two main nonlinear propagation problems encountered by high power CO2 laser radiation in the atmosphere are gas breakdown and thermal blooming. The influence of particulate matter on gas breakdown and also on thermal blooming was investigated. Typical atmospheric conditions contain approximately 1000 particlescc. The presence of these particles in the air path of a high power laser beam can dramatically influence the propagation of the beam. This is illustrated by a photograph which shows particles being vaporized and ionized by a high power pulsed CO2 laser beam. The plasma balls generated not only attenuate the laser radiation, but they also act as scattering centers with completely different scattering characteristics than the original particles. The hot vapor can also act as a thermal source which could cause self-induced thermal distortion of subsequent laser pulses.
- Atmospheric Physics