Granted Patent
Utility
US 6,577,582 · App. 10/021,638
Diffractive stack pickup head for optical disk drives and method to fabricate the pickup head
Inventor:
Mark O. Freeman
Patented Case
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Granted: Jun 10, 2003
Filed: Oct 29, 2001
Inventor
Mark O. Freeman
Assignee (at issue)
Industrial Technology Institute
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.