Patent · US Expired

Method of legitimate product identification and seals and identification apparatus

US5426520A · kind A · utility

22Cited by
7References
3Claims
0Family size

Assignees

Inventors

Key dates

Filing dateNov 2, 1992
Grant dateJun 20, 1995
Priority date
Expiry dateNov 2, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03H1/0011
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A Fourier transform hologram image is created on a sheet on the seal. The image is made, by making a die from the Fourier transform hologram image master plate and by molding resin on the die. The image formed on the sheet is reconstructed by an identification apparatus. The identification apparatus contains the laser emitting device and the screen for receiving the reflecting laser beam. The laser beam is illuminated vertically against the sheet from the laser emitting device. The laser beam reflected from the sheet surface is received by the screen, and the image of the sheet is reconstructed on the screen. At this time, it is possible to check whether the laser beam is reaching the sheet from an opening in the casing.

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