Granted Patent
Utility
US 5,002,354 · App. 07/422,252
High-extinction 2.times.2 integrated optical changeover switches
Inventor:
Kwang-Tsai Koai
Patented Case
View Patent ↗
Granted: Mar 26, 1991
Filed: Oct 16, 1989
Inventor
Kwang-Tsai Koai
Assignee (at issue)
GTE Laboratories Incorporated
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.