Granted Patent
Utility
US 4,645,337 · App. 06/666,948
System for detecting variations in surface composition of an article
Inventor:
Robert J. Obenreder
Patented Case
View Patent ↗
Granted: Feb 24, 1987
Filed: Oct 31, 1984
Inventor
Robert J. Obenreder
Assignee (at issue)
PPG Industries, Inc.
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.