Granted Patent
Utility
US 4,775,229 · App. 06/830,872
Fresnel lens in a finder optical system
Inventors:
Yutaka Ichihara, Daijiro Fujie, Keiji Ohsawa
Patented Case
View Patent ↗
Granted: Oct 4, 1988
Filed: Feb 19, 1986
Inventors
Yutaka Ichihara
Daijiro Fujie
Keiji Ohsawa
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.