Granted Patent
Utility
US 5,408,440 · App. 08/034,364
Hydrophone circuit with electrical characteristics of a geophone
Inventor:
Algernon S. Badger
Patented Case
View Patent ↗
Granted: Apr 18, 1995
Filed: Mar 19, 1993
Inventor
Algernon S. Badger
Assignee (at issue)
Western Atlas International, 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.