Granted Patent
Utility
US 5,757,470 · App. 08/516,521
Variable annular illuminator for photolithographic projection imager
Inventors:
Paul G. Dewa, Paul Francis Michaloski, Paul Jay Tompkins, William N. Partlo
Patented Case
View Patent ↗
Granted: May 26, 1998
Filed: Aug 17, 1995
Inventors
Paul G. Dewa
Paul Francis Michaloski
Paul Jay Tompkins
William N. Partlo
Assignee (at issue)
Federal Signal Corporation
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.