Granted Patent
Utility
US 4,345,928 · App. 06/188,914
Fabrication method of single-mode optical fiber preforms
Inventors:
Masao Kawachi, Satoru Tomaru, Takao Edahiro, Shoichi Suto
Patented Case
View Patent ↗
Granted: Aug 24, 1982
Filed: Sep 19, 1980
Inventors
Masao Kawachi
Satoru Tomaru
Takao Edahiro
Shoichi Suto
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.