 For left circularly polarized light (LCP) with propagation towards the observer, the electric vector rotates counterclockwise.For right circularly polarized light (RCP), the electric vector rotates clockwise.When circularly polarized light passes through an absorbing optically active medium, the speeds between right and left polarizations differ (cL ≠ cR) as well as their wavelength (λL ≠ λR) and the extent to which they are absorbed (εL≠εR).