Title:
METHOD FOR PRODUCING OPTICAL FIBER PREFORM, AND OPTICAL FIBER PREFORM
Document Type and Number:
WIPO Patent Application WO/2024/048356
Kind Code:
A1
Abstract:
This method for producing an optical fiber preform comprises: an addition step in which one or more elements in the alkali metal group are added to the inner surface of a first glass pipe; a collapse step in which the first glass pipe after the addition step is made solid by means of heating, thereby obtaining a glass rod; and a rod-in collapse step in which a rod comprising the glass rod is inserted into a second glass pipe, and the rod and the second glass pipe are integrated with each other by means of heating. The collapse step and the rod-in collapse step are carried out, while traversing an external heat source in a first direction or in a second direction; and in the collapse step and the rod-in collapse step, the difference between the number of times that the heat source is traversed in the first direction and the number of times that the heat source is traversed in the second direction is 1 or less.
Inventors:
SAKUMA HIROTAKA (JP)
KAWAGUCHI YUKI (JP)
SATO SHIN (JP)
HARUNA TETSUYA (JP)
KAWAGUCHI YUKI (JP)
SATO SHIN (JP)
HARUNA TETSUYA (JP)
Application Number:
PCT/JP2023/030043
Publication Date:
March 07, 2024
Filing Date:
August 21, 2023
Export Citation:
Assignee:
SUMITOMO ELECTRIC INDUSTRIES (JP)
International Classes:
C03B8/04; C03B37/012; C03B37/018
Domestic Patent References:
| WO2016013545A1 | 2016-01-28 | |||
| WO2019044833A1 | 2019-03-07 | |||
| WO2013111470A1 | 2013-08-01 |
Foreign References:
| JP2016188151A | 2016-11-04 | |||
| JPS63313105A | 1988-12-21 | |||
| JP2021113134A | 2021-08-05 |
Attorney, Agent or Firm:
HASEGAWA Yoshiki et al. (JP)
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