Granted Patent
Utility
US 4,415,913 · App. 06/271,169
Gray tone recorder
Inventor:
Paul A. Diddens
Patented Case
View Patent ↗
Granted: Nov 15, 1983
Filed: Jun 8, 1981
Inventor
Paul A. Diddens
Assignee (at issue)
Honeywell Limited
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.