A novel method for determining the optical refractive index of fluids

A new technique for determining the refractive index of a fluid (or a gas) is presented. This technique is based on the indirect measurement of the phase shift of orthogonal components of a polarised light beam, caused by a total reflection at the interface of an optically denser medium with an optically thinner medium. In addition, principles of technical set-ups of a measurement probe are described which have neither moving nor electro-optical parts and require only minimal volumes of the analyte.