Patent · US Expired

Discrimination medium, discrimination method, article to be discriminated, and discrimination apparatus

US7943392B2 · kind B2 · utility

3Cited by
7References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 27, 2004
Grant dateMay 17, 2011
Priority date
Expiry dateDec 16, 2025

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB42D2033/26
  • WIPO fieldOther consumer goods
  • WIPO sectorOther fields

Abstract

A discrimination medium cannot be easily falsified. Since the visibility of the discrimination medium is unique, the discrimination medium is superior in determination of the authenticity. The discrimination medium is structured such that a cholesteric liquid crystal layer 106 and a multilayer film 103 having plural light transparent films which are laminated and are different from each other in refraction index are laminated. The reflection light reflected by the discrimination medium includes circular polarization lights which are different in polarization direction, and the discrimination medium has unique optical characteristics. A discrimination method using the above unique optical characteristics, an article to be discriminated by the discrimination medium, and a discrimination apparatus using the above unique optical characteristics are provided.

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