When fabrication of optical surfaces requires motion of the processed surface, it is useful to make a fast measurement of the roughness parameters such as the standard deviation a and the correlation radius A. This can be performed with the help of two devices, in which the processed surfaces are illuminated by high-energy pulsed laser radiation and their coherent images in diffuse scattered light are analyzed. One of the devices provides determination of the standard deviation a and the correlation radius A. for the processed surface in a fixed domain with an accuracy of 10%; the method is valid for roughness heights larger than 10 nm. The second device provides fast measurement of Cr and A in various domains of the surface. These devices can be used to control 0" and A of a optical surface moving in the process of its fabrication such as, for instance, a surface rotating during its mechanical processing. In particular, this is important for fabricating metal mirrors by metal surface sharpening with the help of diamond-tipped cutting tool.
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