Scattering of Directional Light

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Backlight scattering of directional light is mainly a coherent single event effect, considered so far to be a diffusive, multi-event effect. Diffusive scattering must lead to non-uniform images that obey Lambert's Cosine scattering law. However, there are no object images, neither celestial, nor terrestrial, that comply with the law. Observed images are all nearly uniform. The uniformity is a direct outcome of single event scattering. Uniform images of the full moon have been discussed, so far, as diffusive events. Similar images of other bodies have not been discussed. Single event scattering is automatically coherent since a single electromagnetic source wave stimulates all the scattering dipoles. The coherence is responsible to the "Opposition Effect", enhancement of 180 degrees back-scattering by constructive interference. Opposition enhancement has been considered so far as a separate effect from image uniformity. Coherent single event scattering may be separated from non-coherent scattering noise, by interference methods, in order to observe objects such as asteroids, with better resolution or at a higher distance, or to observe bodies within scattering media as in biological tissues.

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