Granted Patent
Utility
US 4,831,640 · App. 07/065,135
Illumination system for x-ray lithography
Inventor:
W. Derek Buckley
Patented Case
View Patent ↗
Granted: May 16, 1989
Filed: Jun 19, 1987
Inventor
W. Derek Buckley
Assignee (at issue)
PerkinElmer, 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.