TOTAL-REFLECTION COEFFICIENT FROM UNIFORM INCIDENT PLANE-WAVES ON A SLAB - THE EFFECT OF MULTIPLE REFLECTIONS

The total reflection coefficient in normal incidence on a slab separat ing any two media is studied from two points of view. In the first, on ly one incident and one reflected wave is taken into account in the fi rst two media. In the second case, multiple reflections and transmissi ons are considered in the three media. In spite of the qualitative dif ferences between the methods, they both lead to the same general value for the total reflection coefficient. This coincidence is explained c learly by considering some intrinsic properties of the waves. A partic ular case is obtained from the general theory developed here: when the third medium is a perfect conductor.