Granted Patent
Utility
US 4,291,287 · App. 06/101,592
Evanescent mode filter
Inventors:
Frederick A. Young, Edward L. Griffin
Patented Case
View Patent ↗
Granted: Sep 22, 1981
Filed: Dec 10, 1979
Inventors
Frederick A. Young
Edward L. Griffin
Assignee (at issue)
Hughes Aircraft Company
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.