Granted Patent
Utility
US 4,561,749 · App. 06/575,154
Focus detection apparatus
Inventor:
Ken Utagawa
Patented Case
View Patent ↗
Granted: Dec 31, 1985
Filed: Jan 30, 1984
Inventor
Ken Utagawa
Assignee (at issue)
Nippon Kogaku K.K.
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.