Optical parameters of vegetable oil studied by terahertz time-domain spectroscopy.

The terahertz time-domain spectra (THz-TDS) of four kinds of vegetable oils were measured in the frequency range extending from 0.2 to 1.5 THz. An iterative algorithm is employed to determine the parameter extraction for terahertz time-domain spectroscopy. The terahertz absorption spectra and refractive indices of four kinds of vegetable oils were analyzed. Compared with the existing data extraction algorithms, the novel iterative algorithm further enhances the accuracy of the parameter extraction for terahertz time-domain spectroscopy.