METHOD AND DEVICE TO MEASURE REFRACTION INDEX Russian patent published in 2015 - IPC G01N21/43 

FIELD: measurement equipment.

SUBSTANCE: invention relates to the field of measurement of refraction index of liquid and paste-like substances using a phenomenon of full internal reflection (limit angle method). The substance of the method consists in the fact that the entire range of measurements of a refraction index with the help of a multi-slot membrane with individual lighting of each slot is broken down into a row of subranges, including a subrange of air refraction index measurement. Prior to measurements of other substances they measure air refraction index, the value of which is taken as a reference. The device comprises a microprocessor with a display, which measures the average value of pulse duration from a line drive to a leading edge in each line, calculates the ratio of this average value to the line period. The produced ratio minus the ratio produced for air is proportionate to refraction coefficient of tested substance.

EFFECT: invention makes it possible to expand the range and to increase accuracy of refraction index measurements.

4 cl, 2 dwg