Granted Patent
Utility
US 4,414,008 · App. 06/329,919
Process for producing optical fiber preform
Inventors:
Takao Edahiro, Tetsuo Miyajiri, Hiroshi Yokota, Toru Kuwahara
Patented Case
View Patent ↗
Granted: Nov 8, 1983
Filed: Dec 11, 1981
Inventors
Takao Edahiro
Tetsuo Miyajiri
Hiroshi Yokota
Toru Kuwahara
Assignees (at issue)
Nippon Telegraph and Telephone Public Corporation
Sumitono Electric Inds., 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.