Patents Assigned to First Ann Arbor Corporation
  • Patent number: 3959884
    Abstract: A method for identifying fingerprints is disclosed; the method produces a descriptor code which is uniquely related to a given fingerprint impression. A fingerprint pattern is transformed into an informational model which represents the relative location of all data points with respect to selected groups of other data points. The method comprises the steps of transforming the fingerprint impression into a representation of a three-dimensional surface wherein the Z-axis coordinate has a value dependent upon the frequency of occurrence of ridge lines at a specific set of X-axis and Y-axis coordinates when the origin is taken at multiple positions over a prescribed part of the fingerprint impression, determining the values of local spatial derivatives, such as the surface curvature of a plurality of different areas of the three-dimensional surface, and concatenating the values in a predetermined order to construct a descriptor code for the fingerprint.
    Type: Grant
    Filed: July 25, 1975
    Date of Patent: June 1, 1976
    Assignee: First Ann Arbor Corporation
    Inventors: Gene M. Jordan, Robert G. Eisenhardt, Dean Z. Douthat