For the present case of air-glass interface, where n₁ < n₂ , the above inequality will hold for

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

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

For , indicating that the reflected light will only be only s polarized. Beyond this

                       ............................................(9)

will be negative and its magnitude will increase with the angle of incidence taking the value of 1 at as shown in fig 3. the negative sign in the region of inequality (7) indicate that the electric field for the reflected wave is out of phase with the corresponding incident wave.