periodic group with an almost ideal elementendiagramm

摘要

A waveguide array comprising a plurality of waveguides which are each outwardly tapered at the aperture of the my in accordance with a predetermined criteria chosen to increase waveguide efficiency. Thc tapering serves to gradually transform a fundamental Bloch mode, propagating through the waveguide array, into a plane wave in a predetermined direction, and then to launch the plane wave into free space in the predetermined direction. In another embodiment, the waveguides are positioned relative to one another in order to satisfy the predetermined criteria.