A rib waveguide structure comprising a layer (4) of light conductive material defined between two planar faces with a rib (9) formed on one of the faces and an optical component e.g. a tapered waveguide (6) optically coupled to the other face. An inverted rib waveguide comprising a light conductive layer...http://www.google.es/patents/US6556759?utm_source=gb-gplus-sharePatente US6556759 - Integrated optical device
