Application of the technique of total integrated scattering of light for micro-roughness evaluation of polished surfaces

The method of light scattering applied to measure the roughness of polished surfaces is based on the statistical evaluation of the light sent by the surface under test; it can therefore characterize the surface as a function of the distribution of scattered light and correlate this distribution with the parameters of roughness. The light scattered by a rough surface contains information about its quality.The scattering measurement technique used in this work is the total integrated scattering (TIS), which measure the ratio of scattered light within a hemisphere covering the surface to be inspected, to the total reflected light by the surface. Then the rms roughness is obtained when it is small compared to the wavelength of light of test.