A device having at least one dielectric inner core region in which electromagnetic radiation is confined, and at least two dielectric outer regions surrounding the inner core region, each with a distinct refractive index. The outer regions confine electromagnetic radiation within the inner core region....http://www.google.es/patents/US6463200?utm_source=gb-gplus-sharePatente US6463200 - Omnidirectional multilayer device for enhanced optical waveguiding
Omnidirectional multilayer device for enhanced optical waveguiding
