Granted Patent
Utility
US 6,442,312 · App. 09/643,684
Optical filter fabrication method and apparatus, optical filter, fiber holder with spiral groove, and phase mask
Inventors:
Yoshitaka Terao, Tsutomu Nomoto, Akihiko Nishiki
Patented Case
View Patent ↗
Granted: Aug 27, 2002
Filed: Aug 24, 2000
Inventors
Yoshitaka Terao
Tsutomu Nomoto
Akihiko Nishiki
Assignee (at issue)
OKI ELECTRIC INDUSTRY 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.