Granted Patent
Utility
US 6,031,324 · App. 09/049,185
Annulus fluorescent lamp
Inventors:
Kenji Itaya, Takeshi Matsumura
Patented Case
View Patent ↗
Granted: Feb 29, 2000
Filed: Mar 27, 1998
Inventors
Kenji Itaya
Takeshi Matsumura
Assignee (at issue)
SUMITOMO ELECTRIC INDUSTRIES, LTD.
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.