Patent · US Active

Method of marking a document or item; method and device for identifyng the marked document or item; use of circular polarizing particles

US8672218B2 · kind B2 · utility

0Cited by
22References
21Claims
0Family size

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Inventors

Key dates

Filing dateApr 27, 2012
Grant dateMar 18, 2014
Priority date
Expiry dateMay 10, 2032

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG07D7/12
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

Optical identification and/or authentication of a document or item with the help of a marking comprising a random distribution of circular polarized light reflecting particles, the marking being applied to the document or item through an ink, and the reading device exploiting circular polarization to discriminate the flakes from the background.

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