Granted Patent
Utility
US 5,392,431 · App. 07/957,256
TV projection lens including a graded index element
Inventor:
Richard Pfisterer
Patented Case
View Patent ↗
Granted: Feb 21, 1995
Filed: Oct 5, 1992
Inventor
Richard Pfisterer
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.