Granted Patent
Utility
US 4,969,157 · App. 06/339,532
Ring laser gyroscope with hollow cathode having frusto-ellipsoidal surface
Inventor:
Alan Malvern
Patented Case
View Patent ↗
Granted: Nov 6, 1990
Filed: Jan 15, 1982
Inventor
Alan Malvern
Assignee (at issue)
British Aerospace Public Limited Co.
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.