A Study on the Beam Wave Transmission

The wave guide using dielectric lenses as phase shifter is one of the fundamental methods of beam wave transmission. The main losses in this system are reflection, diffraction and dielectric ones. Among them, the first is most dominant. But, as for reflection, we know the existence of Brewster angle for plane wave incidence upon plane boundary surface. We may, therefore, expect that the reflection loss will be considerably diminished if lenses are set at Brewster angle with the direction of propagation of the beam wave. To discuss this problem quantitatively we deal, in this paper, with the case when lenses of a kind are set at an arbitrary but constant angle. The beam modes of this system are obtained solving an integral equation. From this the reflection loss is easily calculated if surfaces of lenses are approximated with plane. The results show as expected that the loss is almost neglected. Diffraction loss can also be obtained