Granted Patent
Utility
US 4,307,321 · App. 06/135,605
Red emitting phosphor with slow exponential decay
Inventors:
Romano G. Pappalardo, John Walsh
Patented Case
View Patent ↗
Granted: Dec 22, 1981
Filed: Mar 31, 1980
Inventors
Romano G. Pappalardo
John Walsh
Assignee (at issue)
GTE Laboratories Incorporated
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.