Granted Patent
Utility
US 4,414,012 · App. 06/300,296
Fabrication methods of doped silica glass and optical fiber preform by using the doped silica glass
Inventors:
Shoichi Suto, Hiroyuki Suda, Fumiaki Hanawa, Motohiro Nakahara, Nobuo Inagaki
Patented Case
View Patent ↗
Granted: Nov 8, 1983
Filed: Sep 8, 1981
Inventors
Shoichi Suto
Hiroyuki Suda
Fumiaki Hanawa
Motohiro Nakahara
Nobuo Inagaki
Assignee (at issue)
Nippon Telegraph and Telephone Public 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.