IP Library Granted Patent US 4,892,385
Granted Patent Utility
US 4,892,385 · App. 06/235,970

Sheet-material authenticated item with reflective-diffractive authenticating device

Inventors: William M. Webster, Jr., John P. Russell
Patented Case View Patent ↗
Granted: Jan 9, 1990 Filed: Feb 19, 1981
Inventors
William M. Webster, Jr.
John P. Russell
Assignee (at issue)
General Electric Company

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Quick Facts
Patent No.
US 4,892,385
App. No.
06/235,970
Filed
1981-02-19
Granted
1990-01-09
Kind
A