Surface roughness measurements by means of polychromatic speckle patterns.
A new method for surface roughness measurements is described based on the fibrous, roughness-dependent structure of polychromatic speckle patterns in the far field. The patterns are recorded on photographic film and analyzed by an optical Fourier transform system with a double aperture in the film plane. We have calculated the theoretical roughness dependence of a parameter in the Fourier spectrum. Our experimental results agree fairly well with the theory.
Stansberg
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