Patent · US Expired

Genuineness detecting system and method for using genuineness detecting film

US6628439B2 · kind B2 · utility

50Cited by
7References
25Claims
0Family size

Assignees

Inventors

Key dates

Filing dateApr 27, 2000
Grant dateSep 30, 2003
Priority date
Expiry dateApr 27, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03H2250/41
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An authenticity identifying film (10) has a reflective film (11) having a circularly polarized light selectivity to reflect at least only either of right-handed circularly polarized light and left-handed circularly polarized light of incident light to produce reflected light. The reflective film (11) is provided with a hologram forming part (11a). The hologram forming part (11a) reflects circularly polarized light of the same circular polarization as that of the reflected light in a direction different from that of the reflected light to form a holographic image. The reflected light reflected by the reflective film (11) and the holographic image formed by the hologram forming part (11a) are detected by detectors disposed at different positions, respectively.

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