Granted Patent
Utility
US 6,544,692 · App. 09/700,638
Black defect correction method and black defect correction device for photomask
Inventors:
Osamu Takaoka, Kazuo Aita
Patented Case
View Patent ↗
Granted: Apr 8, 2003
Filed: Feb 26, 2001
Inventors
Osamu Takaoka
Kazuo Aita
Assignee (at issue)
SEIKO INSTRUMENTS 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.