Granted Patent
Utility
US 4,815,831 · App. 06/778,126
Projection lens with color correction
Inventor:
Ellis I. Betensky
Patented Case
View Patent ↗
Granted: Mar 28, 1989
Filed: Sep 20, 1985
Inventor
Ellis I. Betensky
Assignee (at issue)
U.S. Precision Lens Incorporated
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.