Patent · US Expired

Embedded optical signatures in documents

US7252222B2 · kind B2 · utility

14Cited by
31References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 16, 2004
Grant dateAug 7, 2007
Priority date
Expiry dateMay 20, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG07D7/206
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A method of embedding an optical signature in a document and document produced therefrom. The optical signature is an optical pattern generated from a known value, such as a mathematical, geometric, trigonometric, size, phase, and the like, and the same value can be generated from examination of a document having the embedded optical pattern. The document can be validated, authenticated, or the determination of a valid copy of an original document with the embedded optical signature made through comparison of the known value and the value generated from the optical pattern on the document. The optical pattern can also be generated from other identification codes on the document.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.