Granted Patent
Utility
US 5,338,931 · App. 07/872,311
Photoionization ion mobility spectrometer
Inventors:
Glenn E. Spangler, Joseph E. Roehl, Gautam B. Patel, Alvin Dorman
Patented Case
View Patent ↗
Granted: Aug 16, 1994
Filed: Apr 23, 1992
Inventors
Glenn E. Spangler
Joseph E. Roehl
Gautam B. Patel
Alvin Dorman
Assignee (at issue)
Environmental Technologies, LLC
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.