Granted Patent
Utility
US 4,329,261 · App. 06/125,431
Liquid band pass filters
Inventors:
Robert J. Kraushaar, Kevin B. Ward
Patented Case
View Patent ↗
Granted: May 11, 1982
Filed: Feb 28, 1980
Inventors
Robert J. Kraushaar
Kevin B. Ward
Assignee (at issue)
International Standard Electric 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.