Granted Patent
Utility
US 4,425,527 · App. 06/276,449
Optical filters comprising pyrolyzed polyimide films and lamp
Inventor:
Enid K. Sichel
Patented Case
View Patent ↗
Granted: Jan 10, 1984
Filed: Jun 22, 1981
Inventor
Enid K. Sichel
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.