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Identification documents with enhanced security

  • US 7,594,680 B2
  • Filed: 06/03/2004
  • Issued: 09/29/2009
  • Est. Priority Date: 06/03/2004
  • Status: Active Grant
First Claim
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1. A method of producing a security document, comprising:

  • providing a specific security document having a document surface with first information unique to the specific security document formed thereon;

    dividing the first information into a plurality of segments, each segment based on a different portion of the first information; and

    for each segment, forming a diffraction grating layer, each diffraction grating layer having an axis of diffraction that is different from the other diffraction grating layers to form a multi-layered diffractive optically variable image device on the security document, and printing the diffractive optically variable image device on the document surface.

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