Granted Patent
Utility
US 4,865,416 · App. 07/090,863
Optical sensing arrangements
Inventor:
David Pratt
Patented Case
View Patent ↗
Granted: Sep 12, 1989
Filed: Aug 28, 1987
Inventor
David Pratt
Assignee (at issue)
Plessey Overseas Limited
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.