Granted Patent
Utility
US 4,891,507 · App. 07/281,634
Apparatus for extending the infrared response of photocathodes
Inventors:
Joseph Lindmayer, Charles Y. Wrigley
Patented Case
View Patent ↗
Granted: Jan 2, 1990
Filed: Dec 9, 1988
Inventors
Joseph Lindmayer
Charles Y. Wrigley
Assignee (at issue)
QUANEX 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.