Strong Optical Scattering in Atmospheric Turbulence.
Abstract
A versatile and useful facility for simulating the effects of atmospheric turbulence on optical propagation is described and the relevant system parameters characterized. The scattering medium is a turbulent liquid (ethanol) with the turbulence created by unstable convection generated by a strong vertical thermal gradient. Measurements of the structure function and the spatial spectrum of the resulting refractive index fluctuations are presented and compared with the theoretically predicted forms. The effects of this scattering medium on laser beam propagation are determined and compared to the first order Rytov theory. In particular probability density functions, moments and spatial covariance functions of the irradiance resulting from propagation through the system with a variety of turbulence levels and path lengths are presented. The results of an investigation into generating a controlled scattering medium by dispersing uniformly sized transparent spheres in a medium with a slightly different index of refraction is also reported. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 1978
- Accession Number
- ADA062763
Entities
People
- J. Richard Kerr
- Philip A. Pincus
- Richard A. Elliott