Some Notes on Dielectric Waveguide Modes.

Unlike the waveguides with metallic walls, a complete description of the electromagnetic field in dielectric waveguides necessitates consideration of radiant modes. First, radiant modes and characteristic equations governing them and interpreted in terms of geometric optics. The important difference between the metallic and dielectric waveguides is elucidated as far as the cut-off conditions are concerned. The theory of dielectric waveguides of rectangular section is then presented. The possibility of realizing ″networks″ similar to microwave integral circuits, using optical frequencies is indicated. Finally, circular dielectric waveguides are iinvestigated. Satisfactory results are obtained for particular waveguides.