Granted Patent
Utility
US 4,975,895 · App. 07/236,915
Track servo control system for optical disk apparatus
Inventor:
Shigenori Yanagi
Patented Case
View Patent ↗
Granted: Dec 4, 1990
Filed: Aug 26, 1988
Inventor
Shigenori Yanagi
Assignee (at issue)
Fujitsu Limited
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.