Polarization
Circular polarization Looking along the direction of the wave, the electric field traces out the shape of a circle. If the magnitude of the electric field remains constant, and the direction is allowed to vary, the state of polarization is referred to as circular, because the tip of the electric field traces out a circle in the plane perpendicular to the forward direction of the wave. In particular, the circle may be traced out in a clockwise or counterclockwise direction (as the wave is traveling away). (This is similar to swinging a jump rope around for jumping, it makes a circle shape).