US Patent 7057151 Optical transmission apparatus with directionality and divergence control

An apparatus for emitting light with a controlled directionality and optical divergence from at least one opening includes a light impervious surface structure having the at least one opening, a periodic or quasi-periodic surface topography including one or several surface feature(s) and associated with the at least one opening on the surface structure, whereby light emerging from the opening(s) interacts with surface waves on the surface structure (20) thereby providing controlled directionality and optical divergence of the emitted light.