PHOTOELECTRIC METHOD FOR MEASURING THE REFRACTIVE INDEX AND AVERAGE DISPERSION OF MOTOR FUELS AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2023 - IPC G01N21/43 

FIELD: optical instrumentation.

SUBSTANCE: invention concerns a photoelectric method for measuring the refractive index and average dispersion of motor fuels. When implementing the method, the boundary of contact of the fuel under study with the working surface of the measuring prism of a refractometer with refractive index n_D0, average dispersion (Δ_FC)₀ and the angle of inclination of the output face θ, direct a quasi-monochromatic beam of light, use a multi-element photodetector to analyse the light intensity and record the location of the light-shadow boundary. The location of the boundary of light and shadow X_Dx is determined by the inflection point of the light intensity curve and relative to the average value X_Dav corresponding to the average refractive index n_Dav=n_D0sinθ. Based on the data obtained, the required refractive index is determined, taking distortion into account. Next, the wavelength of light is successively changed in the short-wave and long-wave directions, new locations of the boundary of light and shadow are recorded, their difference is determined, and the average dispersion of the fuel under study is calculated from the resulting difference.

EFFECT: increasing the accuracy of measurements of the refractive index and average dispersion of motor fuels.

2 cl, 8 dwg