Detection of a periodic structure embedded in surface roughness, for various correlation functions

摘要

This paper deals with surface pro???lometry, where we try to detect a periodic structure, hidden in randomness using the matched ???lter method of analysing the intensity of light, scattered from the surface. From the direct problem of light scattering from a composite rough surface of the above type, we ???nd that the detectability of the periodic structure can be hindered by the randomness, being dependent on the correlation function of the random part. In our earlier works, we had concentrated mainly on the Cauchy-type correlation function for the rough part. In the present work, we show that this technique can determine the periodic structure of different kinds of correlation functions of the roughness, including Cauchy, Gaussian etc. We study the detection by the matched ???lter method as the nature of the correlation function is varied.