An optical device has a base body with a surface, a first optically effective, multilayer system in the base body, terminating at an intersection, and a second optically effective, multilayer system. The second system has a layer along the base body surface, spanning the intersection. The surface of...http://www.google.es/patents/US6493159?utm_source=gb-gplus-sharePatente US6493159 - Optical element and its manufacturing process
