Infrared image quality can be degraded by atmospheric aerosol scattering. Aerosol interactions are dependent upon the atmospheric conditions and wavelength. Measurements of an edge target at range in the LWIR under hot humid weather provided a blur on the image plane, which is characterized by an MTF. In this experiment, the edge spread function, measured at range, was differentiated to obtain the line spread function and transformed into a MTF. By dividing the total measured MTF by the imager and turbulence MTFs, the aerosol MTF was obtained. Numerical analysis performed using MODTRAN and existing known scattering theory was compared with the experimental results. The measured and numerical results demonstrated a significant aerosol MTF suggesting that the aerosol MTF should be included in sensor performance analysis.
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