Granted Patent
Utility
US 6,698,891 · App. 10/285,431
Polarizing unit, polarizing illumination device using same polarizing unit and projection display device using same polarizing illumination device
Inventor:
Atsushi Kato
Patented Case
View Patent ↗
Granted: Mar 2, 2004
Filed: Nov 1, 2002
Inventor
Atsushi Kato
Assignee (at issue)
NEC Viewtechnology, Ltd.
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.