Wave Optics

any refracted wave and the wave will undergo what is known as total internal reflection. The phenomenon of total internal reflection and its applications was discussed in Section . . FIGURE .

Refraction of a plane wave incident on a rarer medium for which v2 > v1. The plane wave bends away from the normal. . .

Reflection of a plane wave by a plane surface We next consider a plane wave AB incident at an angle i on a reflecting surface MN. If v represents the speed of the wave in the medium and if * represents the time taken by the wavefront to advance from the point B to C then the distance BC = v* In order the construct the reflected wavefront we draw a sphere of radius v* from the point A as shown in Fig. . .

Let CE represent the tangent plane drawn from the point C to this sphere. Obviously