Case2: Normal incidence on a plane dielectric boundary

If the medium 2 is not a perfect conductor (i.e. ) partial reflection will result. There will be a reflected wave in the medium 1 and a transmitted wave in the medium 2.Because of the reflected wave, standing wave is formed in medium 1.

From equation (6.49(a)) and equation (6.53) we can write

..................(6.59)

Let us consider the scenario when both the media are dissipation less i.e. perfect dielectrics ( )

    ..................(6.60)