A substrate having a plurality of light emitting diodes united therewith lies on a plane containing the longitudinal axis of an insertion unit of an endoscope and its neighborhood. Likewise, part of a first objective surface lies on the plane containing the longitudinal axis of the insertion unit of...http://www.google.com/patents/US6656112?utm_source=gb-gplus-sharePatent US6656112 - Distal endoscope part having light emitting source such as light emitting diodes as illuminating means
