When the electric field associated with the wave is given by

              ...........................(13)

The tip of the electric field vector sweeps an ellipse in an anti clock wise direction and such waves are termed as left elliptically polarized waves.

Equation (9) and eq.(13) reduces to eqs. (3) and (7) respectively for = ± /2 and E_0x = E_oy . This means that circular polarized light is an special case of elliptically polarized light.