Granted Patent
Utility
US 6,420,822 · App. 09/354,299
Thermionic electron emitter based upon the triple-junction effect
Inventor:
Robert S. Symons
Patented Case
View Patent ↗
Granted: Jul 16, 2002
Filed: Jul 15, 1999
Inventor
Robert S. Symons
Assignee (at issue)
NORTHROP GRUMMAN CORPORATION
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.