Measurement of roughness exponent for scale-invariant rough surfaces using angle resolved light scattering

Abstract

It is shown that, by modifying the conventional light scattering geometry, it is possible to characterize the root-mean-square roughness w in a scale-invariant rough surface for w values more than one order of magnitude larger than those previously reported. Measurement of w on the order of the wavelength of light has been demonstrated. A consequence of this development is that one can combine the diffraction theory and the measurement to determine the surface roughness exponent α, which was not possible under conventional light scattering conditions.