G02B 6/29388

Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means {characterised by the function or use of the complete device for multiplexing or demultiplexing, i.e. combining or separating wavelengths, e.g. 1xN, NxM for lighting or use with non-coherent light}