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From the problem of rough surface diagnostics, one can establish the set of new actual problems, which must be considered at two levels: 1. Creation of the advanced and improving of the commonly used precise techniques for attestation of a rough surface 2. Further progress of fast-acting techniques for estimating the quality of processing of surfaces, which would provide real-time (or quasi-real-time) control and feasibilities for the correction of the regimes of processing, growing, etching, etc.
An important task in optical characterization of rough surfaces consists of classification of such surfaces into random and fractal ones. As a matter of fact, considerable progress in technologies of formation and processing of high-quality surfaces (e.g., x-ray mirrors) and extension of means for quality control of such surfaces (including electron and atom-force microscopy) put in evidence that the fractal model of a surface structure within the range lower than 100 Ã
is quite adequate. One must suppose that even commonly used rough surfaces, such as glass surfaces processed with abrasive, may be adequately described within the framework of the traditional statistical model and the fractal model within different ranges of heights.
The commonly used techniques for surface processing with an abrasive powder are really of a probabilistic nature with some elements of regularity. It is not surprising that this results in the fact that the height distribution of surface inhomogeneities reflects probabilistic process of processing within the range of sizes of inhomogeneities commensurable with a mean size of abrasive grain (even in the case where sizes of grains of the abrasive differ by two to three orders of magnitude). At the same time, a fine structure of height inhomogeneities of a rough surface, also affected by numerous internal factors (including intermolecular forces of interaction), happens to be close to a fractal one.
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