Granted Patent
Utility
US 3,981,198 · App. 05/593,395
Transducing methods and transducers
Inventor:
Winfield Sample
Patented Case
View Patent ↗
Granted: Sep 21, 1976
Filed: Jul 7, 1975
Inventor
Winfield Sample
Assignee (at issue)
Bell and Howell, LLC
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.