Granted Patent
Utility
US 5,189,342 · App. 07/840,528
Parallel-tuned electronic ballast
Inventor:
Ole K. Nilssen
Patented Case
View Patent ↗
Granted: Feb 23, 1993
Filed: Feb 25, 1992
Inventor
Ole K. Nilssen
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.