Granted Patent
Utility
US 4,396,268 · App. 06/296,508
Dual burst, wide range sonar system
Inventor:
Edwin K. Shenk
Patented Case
View Patent ↗
Granted: Aug 2, 1983
Filed: Aug 26, 1981
Inventor
Edwin K. Shenk
Assignee (at issue)
Polaroid 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.