Granted Patent
Utility
US 5,646,470 · App. 08/343,729
Acoustic transducer
Inventor:
Thomas J. de Groot
Patented Case
View Patent ↗
Granted: Jul 8, 1997
Filed: Nov 22, 1994
Inventor
Thomas J. de Groot
Assignee (at issue)
Benthos, 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.