Granted Patent
Utility
US 5,621,402 · App. 08/095,923
Keypad scanner
Inventors:
Michael E. Spak, Dale E. Gulick
Patented Case
View Patent ↗
Granted: Apr 15, 1997
Filed: Jul 21, 1993
Inventors
Michael E. Spak
Dale E. Gulick
Assignee (at issue)
Advanced Micro Devices, 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.