Effect of precipitation on the transmission of high power laser radiation

Absorption and scattering by gaseous species, aerosol particles and precipitation lead to atmospheric attenuation of laser radiation. High power laser propagation over long horizontal and/or vertical distances is significantly affected by atmospheric attenuation in outdoor locations. Laser transmission experiments can be used to derive experimental extinction coefficients, which can be included in the assessment of the laser safety. However, a full representation of the effect of precipitation types on high power laser propagation is unknown to the authors. Laser transmission experiments at 1030 nm under rainy and snowy weather conditions were performed on a laser test range to investigate the effect of atmospheric attenuation on high power laser radiation. Based on these laser transmission measurements, experimental extinction coefficients were derived. The experimental extinction coefficients are compared with theoretical values. In addition, the experimental extinction coefficients are correlated with visibility measurements.