Granted Patent
Utility
US 5,333,049 · App. 07/804,872
Apparatus and method for interferometrically measuring the thickness of thin films using full aperture irradiation
Inventor:
Anthony M. Ledger
Patented Case
View Patent ↗
Granted: Jul 26, 1994
Filed: Dec 6, 1991
Inventor
Anthony M. Ledger
Assignee (at issue)
Hughes Aircraft Company
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.