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Nowadays skin pathology detection on early stages is one of the progressive directions in medicine. Optical diagnostics methods allow to obtain data on skin's structure and composition,to examine biotissue processes without any negative impact on skin. Polarization diagnostics methods are very perspective. They are of interest due to biotissue-scattered optical fields polarization characteristics' high sensitivity to the structural features and physiological status of the study object. Implementation of quantitative ellipsometry in turbid media eventually can provide qualitatively new results with studies of the tissue's morphological and functional state which relate to the most important directions of today medical diagnostics. As a result development of theoretical and practical aspects of optically heterogeneous biological structures and polarized radiation interaction while solving the tasks of non-invasive rapid medical objects' state control is considered to be of current interest for improving of skin formation detection quality. The purpose of this study is to develop a stand for in vivo skin state examination by scattering ellipsometry with a help of studying of anisotropic skin environment influence on the polarization state evolution of the radiation propagating in this skin.The possibility of implementation the method of quantitative ellipsometry for in vivo skin's optical anisotropy and structural heterogeneity studies is shown. The Mueller matrix algebra is used for describing polarization properties of the depolarizing opticallyactive biotissue medium. A setup for recording the polarization state of the backscattered radiation was designed based on a comparative analysis of the technical options and their application in experiments with biotissue. To have a uniform intensity distribution along the cross section of the input radiation beam, and also to form the polarization states necessary for the study, using the emitting channel of the LEF-3 ellipsometer in the optical scheme of the stand is proposed. The choice of the radiation source wavelength in the spectral range (He-Ne laser, 632 nm) is justified, in which radiation scattering in turbid biological media predominates over absorption, which makes it possible to tell about the sample structural parameters by changing output radiation polarization state. The receiving channel of the output polarization state analyzer was designed, which contains based on a color matrix sensor with a unified analysis field video information block, that allows further multispectral studying of the skin surface structure. The method of a skin ellipsometric examination based on the distribution visualization of the polarization state parameters along the cross section of the output radiation beam and on its subsequent analysis is proposed. For image processing and calculation of the sample polarization characteristics an algorithm and software are developed with a Python language. In the backscattering mode of probing laser radiation the distributions of the skin sector containing scar structures polarization characteristics are obtained.
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