Granted Patent
Utility
US 5,296,881 · App. 07/684,223
Method and contact lenses for treating presbyopia
Inventor:
Michael H. Freeman
Patented Case
View Patent ↗
Granted: Mar 22, 1994
Filed: Apr 12, 1991
Inventor
Michael H. Freeman
Assignee (at issue)
Pilkington Diffractive Lenses 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.