Granted Patent
Utility
US 5,133,028 · App. 07/752,080
Optical wave-length filter and a driving method thereof
Inventors:
Hideaki Okayama, Hiroki Yaegashi, Toshimasa Ishida
Patented Case
View Patent ↗
Granted: Jul 21, 1992
Filed: Aug 29, 1991
Inventors
Hideaki Okayama
Hiroki Yaegashi
Toshimasa Ishida
Assignee (at issue)
OKI ELECTRIC INDUSTRY CO., LTD.
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.