Granted Patent
Utility
US 6,816,449 · App. 09/930,963
Optical pickup compatible with a digital versatile disk and a recordable compact disk using a holographic ring lens
Inventors:
Jang-hoon Yoo, Chul-woo Lee
Patented Case
View Patent ↗
Granted: Nov 9, 2004
Filed: Aug 17, 2001
Inventors
Jang-hoon Yoo
Chul-woo Lee
Assignee (at issue)
SAMSUNG DISPLAY CO., LTD.
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.