The Effects of the Atmosphere on Light and on Propagating Laser Beams

The atmosphere affects light propagation in many ways. Temperature and density distributions, aerosols, and ice crystals produce many interesting optical phenomena such as mirages, "sun dogs," the fata morgana, light pillars, and the green flash. Atmospheric turbulence leads to the shimmering of objects, the twinkling of the stars, and especially the distortion of laser beams propagating through the atmosphere.
 
A fundamental understanding of these atmospheric effects is very important for optimizing the operation of free space optical (FSO) communication systems, for imaging through the atmosphere, and in the operation of laser weapons. Specifically, the atmosphere distorts the beam from a laser and reduces the power reaching a target. There is great interest in ways to mitigate the effects of this beam distortion.  
 
In this talk I will discuss these topics and some of the modeling and measurement techniques that are used to describe the effects of the atmosphere, especially turbulence, on propagating laser beams.

Speaker:Chris Davis, Univ. of Maryland