Granted Patent
Utility
US 4,977,549 · App. 07/246,776
Write and erase magnetic bias field switching system for a magneto-optic disk drive
Inventor:
Thomas E. Berg
Patented Case
View Patent ↗
Granted: Dec 11, 1990
Filed: Sep 20, 1988
Inventor
Thomas E. Berg
Assignee (at issue)
Hewlett-Packard Company, L.P.
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.