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Stokes parameters were measured for radiation reflected in the range 5° to 80° by silver-colored, white, and black thermal control coatings deposited on an aluminum alloy substrate, by green paint on a phenolic plastic surface, and by uncoated carbon-fiber reinforced plastic illuminated by linearly polarized He–Ne laser radiation at an incident angle of –5°. The bidirectional reflectance distribution function of the investigated samples was determined as a function of the view zenith angle.

Polarization was examined in laser light reflected from samples of plant leaves. Elliptical polarization is supposed to result from multiple total reflections of the incident light on the inhomogeneities of the leaf cuticle. A model of the phase-shifting ability of the scattering layer allows assessment of the refractive index and the mean facet slope of cuticular roughness.

A paper for offset printing was exposed to radio frequency discharge plasma and radio frequency electromagnetic field. Optical response and structural features of paper before and after the treatment have been investigated by several techniques: digital laser speckle photography, laser Stokes polarimetry and attenuated total reflectance (ATR). The changes of statistical distributions of speckle patterns has been observed for plasma treated paper as a result of increase of correlative dimensions of structural heterogeneity of modified paper. It is shown also that the radio wave treatment leads to anisotropy reduction in the paper structure that is more apparent if the magnetic field lines are oriented transversely to the plane of a paper sheet.