Abstract

Measurements of the opposition effect (brightening in the retroreflectance direction) have been extended to geometries with the normal of reflecting surface tilted up to 60° from the incident direction. Surface tilt appears to have little or no effect on the retroreflecting properties of MgCO₃, BaSO₄ paint, colloidal sulfur, or white Nextel paint for 0.6328-μm laser or 0.6-μm low coherence illumination. Source collimation–sensor acceptance angle decrease from 1° with 0.6328-μm laser illumination increases the opposition effect. The theoretical explanation of the effects observed may lie in the use of the Mie theory for highly collimated incident radiation.

© 1977 Optical Society of America

Retroreflectance measurements of photometric standards and coatings

W. G. Egan and T. Hilgeman
Appl. Opt. 15(7) 1845-1849 (1976)

Laser retroreflectance consistent with a polarized single-scatter weak electromagnetic-field localization-interference phenomenon

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Experimental study of the opposition effect in the scattering of light from a randomly rough metal surface

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Integrating Spheres for Measurements Between 0.185 μm and 12 μm

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Infrared thermooptic coefficient measurement of polycrystalline ZnSe, ZnS, CdTe, CaF₂, and BaF₂, single crystal KCl, and TI-20 glass

R. J. Harris, G. T. Johnston, G. A. Kepple, P. C. Krok, and H. Mukai
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