SKEDSOFT

Physics For Engineers - 1

Equation (6) represents the equation of circle. There fore we can describe the wave given by equation (2) as a wave whose direction of electric field is rotating in x-y plane with the angular frequency , the frequency of the wave and the tip of the electric field vector is moving in a circle in clock wise direction as shown in the fig 1 below.

fig..(1)

This kind of wave is termed as right circularly polarized light.

Suppose that the phase difference is such that equation 2 reduces to

                  ............................ (7)

In the above case the tip of the electric field will be encircling with a frequency but in anti clockwise direction as shown in fig 2. This kind of wave represented by eq 7 is termed as left circularly polarized light.

From eq 3 and 7, the circularly polarized light can be generated by super position of two orthogonal polarization of same amplitude and frequency but having a phase gap of .

Superposition of two circularly polarized light:

Let us consider a situation where right circularly (eq 3) and left circularly polarized light (eq 7) are superimposed. The resultant field is

                     ................................... (8)

The equation (8) represent as plane wave. Thus a plane wave can be synthesised by super position of two oppositely circular polarized light of equal amplitude and frequency.