Granted Patent
Utility
US 5,986,995 · App. 09/234,620
High NA catadioptric focusing device having flat diffractive surfaces
Inventors:
Chuan He, Hong Chen, Charles C. Cheng
Patented Case
View Patent ↗
Granted: Nov 16, 1999
Filed: Jan 21, 1999
Inventors
Chuan He
Hong Chen
Charles C. Cheng
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.