Granted Patent
Utility
US 4,390,817 · App. 06/238,771
Integratable CRT spot cut-off network
Inventor:
Fred D. Johnson
Patented Case
View Patent ↗
Granted: Jun 28, 1983
Filed: Feb 27, 1981
Inventor
Fred D. Johnson
Assignee (at issue)
Zenith Radio 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.