Granted Patent
Utility
US 4,915,717 · App. 06/577,405
Method of fabricating optical fiber preforms
Inventors:
Minoru Watanabe, Naoki Yoshioka, Hiroo Kanamori, Nobuo Inagaki
Patented Case
View Patent ↗
Granted: Apr 10, 1990
Filed: Feb 6, 1984
Inventors
Minoru Watanabe
Naoki Yoshioka
Hiroo Kanamori
Nobuo Inagaki
Assignees (at issue)
Tokyo Nippon Telegraph Public Corporation
SUMITOMO ELECTRIC INDUSTRIES, 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.