The polarization of light waves

The snapshot pattern of the propagating wave is a helix, and the sectional pattern is a circle. By the most common convention, if the hght is viewed looking toward the source and the E vector rotates clockwise, then the polarization is called right-hand circular . Accordingly, for a counter-clockwise E-vector rotation the polarization would be called left-hand circular . 

Note that, by convention, a linear polarized hght wave is often termed n-polarization, and right-hand and left-hand circular-polarized waves are termed and O -polarization respectively. These are of great importance when considering photon transition probabihties and selection rules in atoms and molecules. 

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