Granted Patent
Utility
US 4,258,394 · App. 05/828,057
Digital circuit for accurately detecting changes in the gray scale of a scanned image
Inventor:
Paul Kennedy
Patented Case
View Patent ↗
Granted: Mar 24, 1981
Filed: Aug 26, 1977
Inventor
Paul Kennedy
Assignee (at issue)
Westinghouse Electric Company LLC
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.