Sheet-material authenticated item with reflective-diffractive authenticating device
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Jan 9, 1990
Grant Date -
N/A
app pub date -
Feb 19, 1981
filing date -
Feb 19, 1981
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
An improved authenticating device comprises a substrate bonded to the sheet material, the substrate having a reflective diffractive structure formed as a relief pattern on a viewable surface thereof, and a transparent material covering the structure. Specified grating parameters of the diffractive structure, obtainable at low cost, result in peculiar, but easily discernable, optical color properties that cannot be copied by color copying machines.
First Claim
Family
International Classification(s)
- [Classification Symbol]
- [Patents Count]
Cited Art Landscape
Patent Citation Ranking
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully