Patents Assigned to EDI of Louisiana, Inc.
  • Patent number: 5532771
    Abstract: An optical scanner (100) includes a rotating scanner disk (116) that integrates a multifocal Fresnel fixation lens (114), a Fresnel optical scanner (122, 124), and an angular position encoder (140) into a unitary, inherently aligned, compression-molded component. An individual being identified views through the multifocal Fresnel fixation lens an image of a pinhole (108) illuminated by a light source (104). The multifocal lens is centered on the disk and creates multiple in- and out-of-focus images (180, 182, 184, 186) of the pinhole image. The combined image appears to the individual as a set of circular images (190, 192, 194, 196), one of which is in focus. The images appear concentric when the individual is properly aligned with the disk and associated optics. The Fresnel optical scanner receives IR light from the light source and creates an IR scanning beam (126) when the disk is rotated.
    Type: Grant
    Filed: December 17, 1993
    Date of Patent: July 2, 1996
    Assignee: EDI of Louisiana, Inc.
    Inventors: Joel C. Johnson, Robert B. Hill