An apparatus for imaging a finger so as to produce a fingerprint image free of artifacts created by moisture on the finger. An optical platen having a surface for receiving the finger to be imaged is illuminated by a light source. A light detector is provided for receiving light from the platen surface...http://www.google.ca/patents/US5416573?utm_source=gb-gplus-sharePatent US5416573 - Apparatus for producing fingerprint images which are substantially free of artifacts attributable to moisture on the finger being imaged
