I have been working with the NSC ray-tracer and trying to model a surface that scatters a laser into random polarization and direction- something like a Spectralon surface at normal incidence. The lambertian surface works well with a random polarized light but for some reason when I use polarized radiation the polarization is more or less conserved after reflection. Is there an easy way to create a surface where polarization is not conserved? Can this surface be partially scattering where say ½ the light undergoes specular polarization conserving reflection and the other ½  is scattered (lambertian) and polarization is not conserved?

Thanks!

Bram