An exit sign comprising a housing and a plurality of red and green color LEDs having the capability of being selectively activated to produce either red light or green light. The plurality of LEDs are mounted in a mutual lighting association in the housing. A switch is manually operable to selectively...http://www.google.se/patents/US7114840?utm_source=gb-gplus-sharePatent US7114840 - Exit sign illuminated by selective color LEDs
