Patent ID: 6191410
Filing Date: 2001-02-20
Classification: A61B,G06K

Abstract:
Apparatus for sensing fingerprints comprising:a) fingerprint differentiation means for internally reflecting illuminating radiation from points of illumination on a contact surface of the fingerprint differentiation means corresponding to fingerprint valleys in one or more fingers of the subject pressed in a contact zone on the contact surface, and for transmitting illuminating radiation through the contact surface at points of illumination corresponding to fingerprint ridges in the fingers of the subject;b) illuminating means affixed to the fingerprint differentiation means for internally illuminating the contact surface with a plurality of sub-beams of illuminating radiation, the angle of incidence of the sub-beams to the contact surface being selected to provide for reflection of the sub-beams from points of illumination corresponding to fingerprint valley points and transmission of sub-beams through the contact surface at fingerprint ridge points which contact the contact surface;c) sensing means affixed to the fingerprint differentiation means for sensing sub-beams reflected from the contact surface and generating an electric signal for each sub-beam received.