Field and Wave Electromagnetics 2nd Edition by David Cheng

Exercise 56

Dielectric lenses can be used to collimate electromagnetic fields. In Fig. 3-30 the left surface of the lens is that of a circular cylinder, and the right surface is a plane. If E 1 at point P ( r o , 45°, z ) in region 1 is a r 5 a 3, what must be the dielectric constant of the lens in order that E 3 in region 3 is parallel to the x -axis