Abstract: 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 which is internally reflected at the surface. A fingerprint image is formed by light which is internally reflected at the regions intermediate the finger ridges and absorbed/dispersed where the ridges contact the surface, The observation angle of the detector is sufficiently large so that moisture on a person's fingers does not affect the light which is internally reflected at the surface and detected. The resultant fingerprint image is free of artifacts attributable to moisture.

Abstract: A fingerprint imaging apparatus for use in an identity verification system or the like. The imaging apparatus includes a carriage rotatably mounted on a frame, with the carriage being driven by a stepper motor. A transparent optical element having an arcuate recess for receiving a finger to be imaged is secured to the frame. The rotatable carriage supports a light source and mirror which are positioned adjacent the optical element. The mirror is positioned with respect to the source and optical element to receive light issuing from the element which originated from the source. The light is reflected by the mirror through a lens arrangement to a second mirror and then to a linear photo-diode array which are also mounted on the carriage. When a finger is positioned in the recess of the optical element, the motor causes the carriage to rotate so that the finger is scanned by the light source. The linear diode-array is periodically read out during the scan with the output of the array containing imaging data.