Granted Patent
Utility
US 4,675,959 · App. 06/735,025
Production of piezoelectric dielectric films by poling in stack form
Inventor:
Oliver S. Sprout, Jr.
Patented Case
View Patent ↗
Granted: Jun 30, 1987
Filed: May 17, 1985
Inventor
Oliver S. Sprout, Jr.
Assignee (at issue)
Pennwalt Corporation
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.