An illuminating system for endoscopes wherein, in order that a very wide range of the field of view of an observing system may be uniformly illuminated, a light guide and a bar-shaped reflector are so arranged that the optical axis of at least one of the light guide and bar-shaped reflector may not intersect...http://www.google.se/patents/US4403273?utm_source=gb-gplus-sharePatent US4403273 - Illuminating system for endoscopes