Granted Patent
Utility
US 4,817,430 · App. 07/130,083
System for determining the thickness of varying material coatings
Inventors:
Ewald Benes, Paul Berlinger, Gernot Thorn
Patented Case
View Patent ↗
Granted: Apr 4, 1989
Filed: Dec 8, 1987
Inventors
Ewald Benes
Paul Berlinger
Gernot Thorn
Assignee (at issue)
Leybold GmbH
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.