Characterizing The Effect of Artificial Aerosols on The Performance of a Thermal Imaging System

Abstract

Artificial aerosols have major impact affecting the electromagnetic (EM) radiation propagation, and as a result, thermal imaging systems operate poorly. Artificial aerosols absorb and disperse electromagnetic waves, which causes these effects. According to the classic theory of EM scattering, We develop a model to evaluate the effectuation of absorption and scattering on the propagation of infrared radiation from the object to the imaging system. The quantity of power received to form the image is reduced as a result of absorption. Scattering, on the other hand, has the effect of uncorrelating the IR radiation leaving the target from the unscattered radiation that reach the imaging plane, as well as widening the angle of the received scattered IR radiation when compared to the received unscattered IR radiation. Both of these effects are dependent on the type of aerosol present, as well as its EM characteristics and wavelength. We use our model to calculate an imaging system’s average point spread function (PSF), which takes into account the effects of scattering, the power level of both unscattered and scattered light arriving at the imaging system, and also diffraction. The main finding of this study is that artificial aerosol scattering and absorption have a significant impact on the spatial resolution and contrast of the constructed images acquired by thermal imaging systems, owing to an increase in the incoherent (scattered) radiation PSF and a decrease in the coherent (direct) radiation PSF due to the increase of aerosol optical depth (AOD).