Granted Patent
Utility
US 4,521,069 · App. 06/364,486
Optical switch
Inventor:
Masahiro Ikeda
Patented Case
View Patent ↗
Granted: Jun 4, 1985
Filed: Apr 1, 1982
Inventor
Masahiro Ikeda
Assignee (at issue)
Nippon Telegraph and Telephone Public 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.