Granted Patent
Utility
US 4,900,119 · App. 07/176,683
Wavelength selective optical devices using optical directional coupler
Inventors:
Kenneth O. Hill, Derwyn C. Johnson, Francois Bilodeau, Sylvain Faucher
Patented Case
View Patent ↗
Granted: Feb 13, 1990
Filed: Apr 1, 1988
Inventors
Kenneth O. Hill
Derwyn C. Johnson
Francois Bilodeau
Sylvain Faucher
Assignee (at issue)
Canadian Patents and Development Limited
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.