FIELD: optical measurements, determination of color of objects with partially clear internal medium diffusely scattering light, specifically, teeth. SUBSTANCE: procedure determining color of objects consist in coaxial delivery of radiation for illumination of surface of object relative to receiving light guide which input window is set directly on surface of object prior to illumination of surface of object or at distance of not more than 5.0 mm and in registration of radiation across output of receiving light guide which parameters are used to make decision on color of object. Radiation is so formed that incidence angles of light beams passing through circle lying in plane of input window of receiving light guide with center matching geometrical center of input window of receiving light guide do not exceed 25 degrees with plane of circle mentioned above which diameter should exceed diameter of input window of receiving light guide by 1.0 mm or more. Facility includes illumination unit with output window, unit registering radiation connected to unit of control and signal processing which output is connected to input of illumination unit, receiving light guide that protrudes from output window of illumination unit by value of diameter of output window as minimum and which output window is optically coupled to input of unit registering radiation. Output window of illumination unit and receiving light guide are installed coaxially one another and input window of receiving light guide is designed for mounting on surface of object. EFFECT: provision for objective automated determination of color of such objects as teeth. 3 cl, 5 dwg
