Holographic Method for Reconstruction of Random Rough Surface

A holographic principle for computer reconstruction of random rough surface (RRS) and determination of the surface parameters is used. The random function describing the surface is expanded in a Fourier series. The scattering from the RRS light field is approximated as a field, obtained as result of diffraction from sinusoidal gratings. The mixed field (obtained from the mixing of the diffracted field and the field of the laser beam) carries information about the phase of each sinusoidal grating. Sections of the diffracted and mixing fields are correspondingly registered by photodiode array. The first, the second and the third diffraction orders from each grating are taken into account for the surface reconstruction. The statistical distribution and the autocorrelation function of the surface height fluctuation are calculated. The surface parameters of mean roughness, root mean square and correlation length are determined. The studied surface, having a Gaussian statistic, is measured from the work of Daintyet al.Talystep profilometer. The values of the above-mentioned surface parameters calculated in Daintyet al.are in good agreement with those obtained in the present work.