A new method for measuring the chiral parameter and the average refractive index of a chiral liquid

Abstract

We designed a method for measuring chiral parameter and average refractive index of an isotropic chiral medium using critical angle phenomena. Linearly polarized light is guided to project onto the interface of a semi-spherical glass and a chiral liquid. The reflected light passes through an analyzer to extract the interference signal of s- and p-polarization lights. Their phase difference is first optimized by a suitable optical arrangement and subsequently measured by a heterodyne interferometer. The result, then, is fed into equations to estimate the chiral parameter. We determine the average index of refraction from the critical angle occurred at the discontinuity of the phase difference of two polarized lights. Our method of measurement has the implicational merits of both common-path interferometry and heterodyne interferometry. (C) 2003 Elsevier Science B.V. All rights reserved.