Granted Patent
Utility
US 4,940,889 · App. 07/394,130
Method and apparatus for visual indication of optical alignment of photoelectric switch
Inventors:
Shoichi Ono, Atsuhito Kobayashi
Patented Case
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Granted: Jul 10, 1990
Filed: Aug 15, 1989
Inventors
Shoichi Ono
Atsuhito Kobayashi
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.