Granted Patent
Utility
US 4,881,050 · App. 07/228,288
Thin-film microwave filter
Inventor:
Daniel G. Swanson
Patented Case
View Patent ↗
Granted: Nov 14, 1989
Filed: Aug 4, 1988
Inventor
Daniel G. Swanson
Assignee (at issue)
Avantek, 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.