Optical transmission devices suitable for use in constructing lightpipe networks are disclosed. The optical transmission devices include an optical coupler arrangement (1, 34, 72, 73) for connecting a lightpipe to other optical transmission or utilization devices with minimum interface losses. A lens...http://www.google.ca/patents/US4496211?utm_source=gb-gplus-sharePatent US4496211 - Lightpipe network with optical devices for distributing electromagnetic radiation
