Granted Patent
Utility
US 5,228,440 · App. 07/598,850
Fetal pulse oximetry apparatus and method of use
Inventors:
Christopher Chung, Helen M. McNamara
Patented Case
View Patent ↗
Granted: Jul 20, 1993
Filed: Oct 15, 1990
Inventors
Christopher Chung
Helen M. McNamara
Assignee (at issue)
Nellcor 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.