METHOD OF CONTROLLING ANISOTROPY OF ANGULAR DISTRIBUTION OF FIBRES IN STRUCTURE OF FLAT FIBROUS MATERIAL Russian patent published in 2012 - IPC G01N21/00 G01N33/34 G01N33/36 

FIELD: physics.

SUBSTANCE: image of the surface of analysed material on a transparent base is illuminated with a parallel light beam perpendicular its surface and distribution of light flux which has passed through said image is analysed in the corresponding Fraunhofer diffraction pattern. Angular dependence of light flux in the diffraction pattern, which has fallen into a ring with radii R₁, R₂ (R₂ > R₁), whose centre coincides with the central maximum of the diffraction pattern, is determined, and anisotropy of the angular distribution of fibres in the analysed material is determined from said dependence.

EFFECT: broader capabilities of the diffraction method of finding, from a Fraunhofer diffraction pattern, the function of angular distribution of fibres for materials having chaotic distribution of fibres in a geometrical structure, regardless of its optical properties, thickness and physical nature of fibres inside the material.

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