Determined optical constants of liquid hydrocarbon fuel by a novel transmittance method

A method for experimentally determining optical constants of liquid hydrocarbon fuel was proposed, based on inversing transmittance of optical cell consisted of two glass slabs and a liquid sample layer. The method was validated by experimentally determining optical constants of water. Then measurements of transmittance spectrogram of optical cell with different thicknesses of Chinese diesel fuel in the infrared wavelength 1.3–3.2 μm at normal incidence were investigated by a Bruke V70 FTIR spectrometer. The optical constants of Chinese diesel fuel were achieved by the experimental method. The results indicate that the optical constants of water determined by the method have good agreement with previously data sets. And the optical constants of Chinese diesel fuel have remarkable difference with the others diesel fuel published.