Granted Patent
Utility
US 5,608,470 · App. 08/494,872
Prescription lens attachable to safety glasses
Inventor:
Keith W. Sheffield
Patented Case
View Patent ↗
Granted: Mar 4, 1997
Filed: Jun 26, 1995
Inventor
Keith W. Sheffield
Assignee (at issue)
Crews, 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.