Measurement of Complex Dielectric Constant Using Optical Method

This paper describes a method for determination of complex dielectric constant of an optically absorbing medium. We have put down basic formulae for estimation of real and imaginary parts of dielectric constant using Fresnel's reflection equation for p-polarized light at intensity minimum. The experiment involves precise determination of pseudo-brewster angle and the corresponding intensity minimum. The complex dielectric constant is estimated to be $\hat{\varepsilon}=-8.83-i 13.19$ . The uncertainty analysis for measurements has also been carried out. The present technique has the advantage of being easy to operate and having improved uncertainty.