METHOD OF MEASUREMENT OF REFRACTIVE INDEX OF TRANSPARENT AND ABSORBING MEDIA Russian patent published in 1996 - IPC

FIELD: refractometric measurements of optical constants of media. SUBSTANCE: method of measurement of refractive index of transparent and absorbing media lies in direction of monochromatic light beam on to boundary of contact of examined medium with known refractive index, in change of incidence angle, in registration of intensity of reflected light and in determination of pseudocritical incidence angle by which desired refractive index is found. For determination of point of knee on curve of dependence of intensity of reflected light on incidence angle there is conducted differentiation with variable step by computation of difference between summary values of function increments with increment of argument on the right and on the left relative to i-th point of argument. Number of steps to the right or left with reference to i-th point depends on slope of curve, that is on value of absorption coefficient of examined medium. As result of summation of small increments one manages to get rid of influence of fluctuations as noises are averaged. EFFECT: enhanced authenticity of method. 3 dwg