Granted Patent
Utility
US 4,725,137 · App. 06/546,611
Process and apparatus for measuring an evanescent field in an optical fiber
Inventor:
Donald Schmadel
Patented Case
View Patent ↗
Granted: Feb 16, 1988
Filed: Oct 28, 1983
Inventor
Donald Schmadel
Assignee (at issue)
Chevron Research 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.