Granted Patent
Utility
US 6,181,485 · App. 09/338,888
High numerical aperture optical focusing device for use in data storage systems
Inventor:
Chuan He
Patented Case
View Patent ↗
Granted: Jan 30, 2001
Filed: Jun 23, 1999
Inventor
Chuan He
Assignee (at issue)
Read Rite Corporation
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.