By definition: ''An electromagnetic wave such as light consists of a coupled oscillating electric field and magnetic field which are always perpendicular; by convention, the "polarization" of electromagnetic waves refers to the direction of the electric field. In linear polarization, the fields oscillate in a single direction. In circular or elliptical polarization, the fields rotate at a constant rate in a plane as the wave travels. The rotation can have two possible directions; if the fields rotate in a right hand sense with respect to the direction of wave travel, it is called right circular polarization, or, if the fields rotate in a left hand sense, it is called left circular polarization.'' My understanding is that there are always the 2 components (2 perpendicular vectors) that rotate only clockwise!

Dear Domenico:

Thank you very much for your answer.

Regards.

Adnan

In CD, a plane polarized light passes through the sample. A plane polarized light may be thought of as a combination of a right and a left circularly polarized light of same intensity and phase. Now, if the intensity or phase of any of the component changes the transmitted light becomes eliptically polarized. This animated tutorial may help to understand this phenomenon: http://cddemo.szialab.org/