We present an improved method for material classification by measurement of the full Stokes vector of a reflectance image. This approach is based on the observation that linearly polarized light specularly reflected from a dielectric remains linearly polarized but becomes highly unpolarized in off- specular directions. For a metal, the same incident light becomes elliptically polarized on reflection in both the macroscopic specular and non-specular directions except when the orientation of polarization of the incident light is perpendicular to or parallel to the plane of incidence. The novelty and value in comparison with previous approaches is that it removes a number of constraints on system and scene geometry.

Date Published: 16 September 1999
PDF: 10 pages
Proc. SPIE 3826, Polarization and Color Techniques in Industrial Inspection, (16 September 1999); doi: 10.1117/12.364328

Published in SPIE Proceedings Vol. 3826:
Polarization and Color Techniques in Industrial Inspection
Elzbieta A. Marszalec; Emanuele Trucco, Editor(s)