Extraction of height probability density of random rough surfaces from the central δ-peak of angle-resolved light scattering using the optical inversion algorithm

We developed a method for extracting the height probability density of random surfaces by light scattering. Theoretical results show that height probability function is the Fourier transform of the central delta-peak in the light waves of angle-resolved light scattering. Experimentally, we measure the delta-peak intensities at a different angle of incidence in a simple setup. We then reconstruct the phase distributions of the delta-peak versus the perpendicular component of the wave vector from the intensities using the Gerchberg-Saxton inversion algorithm, and then extract the height probability density of the samples. Two different types of samples are measured to verify the validity of the method, and the results are compared with those obtained by atomic force microscopy. (C) 2002 American Institute of Physics.