Granted Patent
Utility
US 4,954,318 · App. 07/091,432
Optical sensor
Inventors:
Masao Yafuso, Cheng F. Yan, Thomas G. Hacker, Henry K. Hui, Thomas P. Maxwell, William W. Miller
Patented Case
View Patent ↗
Granted: Sep 4, 1990
Filed: Aug 31, 1987
Inventors
Masao Yafuso
Cheng F. Yan
Thomas G. Hacker
Henry K. Hui
Thomas P. Maxwell
William W. Miller
Assignee (at issue)
Minnesota Mining and Manufacturing Company
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.