Patent · US Expired

System for verifying authenticity of various articles

US4837840A · kind A · utility

39Cited by
14References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 26, 1987
Grant dateJun 6, 1989
Priority date
Expiry dateFeb 26, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG07F7/08
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

Representations are developed that characterize an article for identification by comparison with a reference standard as an escort memory. The representations are reduced to a binary tri-level code covering two extreme possibilities and an intermediate range for indecisive cases. Characteristics are sensed by light in one form by interferometer techniques.

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