Granted Patent
Utility
US 6,213,625 · App. 09/298,298
Inverted apex prismatic lens
Inventors:
Kevin F. Leadford, Carl T. Gould
Patented Case
View Patent ↗
Granted: Apr 10, 2001
Filed: Apr 23, 1999
Inventors
Kevin F. Leadford
Carl T. Gould
Assignee (at issue)
NSI Enterprises, 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.