Method for manufacturing multicore optical fiber

Patent metadata

Field	Value
Publication number	US-11059737-B2
Application number	US-201916364593-A
Country	US
Kind code	B2
Filing date	Mar 26, 2019
Priority date	Mar 27, 2018
Publication date	Jul 13, 2021
Grant date	Jul 13, 2021

Abstract

A method for manufacturing a multicore optical fiber includes a step of forming ring-shaped closed-end holes to axially extend from a first end toward a second end of a glass rod; a step of heating bottom parts of the ring-shaped closed-end holes and softening center rods surrounded by the ring-shaped closed-end holes; a step of pulling out the center rods toward a side of the first end, forming columnar closed-end holes from the ring-shaped closed-end holes, and treating the glass rod as a cladding material; a connecting step of connecting a supporting pipe to the first end; an inserting step of inserting core rods into the columnar closed-end holes after the connecting step; and a drawing step of drawing the cladding material and the core rods while heating a portion near the second end and integrating the cladding material and the core rods after the inserting step.

First claim

What is claimed is:

1. A method for manufacturing a multicore optical fiber, the method comprising:
a step of forming a plurality of ring-shaped closed-end holes to extend from a first end toward a second end in an axial direction of a glass rod;
a step of heating bottom parts of the plurality of ring-shaped closed-end holes and softening a plurality of center rods that each are surrounded by a corresponding one of the plurality of ring-shaped closed-end holes;
a step of pulling out the plurality of center rods toward a side of the first end, forming a plurality of columnar closed-end holes from the plurality of ring-shaped closed-end holes, and treating the glass rod as a cladding material;
a connecting step of connecting a supporting pipe to the first end of the cladding material;
an inserting step of inserting core rods into the plurality of columnar closed-end holes in a one-to-one correspondence after the connecting step; and
a drawing step of drawing the cladding material and the core rods while heating a portion near the second end of the cladding material and integrating the cladding material and the core rods after the inserting step.

2. The method for manufacturing a multicore optical fiber according to claim 1 ,
wherein the step of pulling out the center rods includes pulling out the center rods in a state where the glass rod vertically stands while the first end faces downward.

3. The method for manufacturing a multicore optical fiber according to claim 2 , further comprising a step of removing residues remaining in the columnar closed-end holes after the step of pulling out the center rods.

4. The method for manufacturing a multicore optical fiber according to claim 3 , further comprising a step of washing inside of the columnar closed-end holes after the step of removing the residues remaining in the columnar closed-end holes.

5. The method for manufacturing a multicore optical fiber according to claim 1 ,
wherein the step of softening the center rods includes arranging the bottom parts in a heater.

6. The method for manufacturing a multicore optical fiber according to claim 5 ,
wherein the step of pulling out the center rods includes pulling out the center rods in a state where the glass rod vertically stands while the first end faces downward.

7. The method for manufacturing a multicore optical fiber according to claim 6 , further comprising a step of removing residues remaining in the columnar closed-end holes after the step of pulling out the center rods.

8. The method for manufacturing a multicore optical fiber according to claim 7 , further comprising a step of washing inside of the columnar closed-end holes after the step of removing the residues remaining in the columnar closed-end holes.

Assignees

• Sumitomo Electric Industries

Inventors

• Nakanishi Tetsuya
• Nagashima Takuji

Classifications

• C03B37/01257

  Heating devices therefor · CPC title

• C03B37/01222 Primary

  for making preforms of multiple core optical fibres (preforms of multifibres C03B37/01214) · CPC title

• C03B37/027

  Fibres composed of different sorts of glass, {e.g. glass optical fibres}(C03B37/0253, C03B37/028 take precedence) · CPC title

• G02B6/03627

  arranged - + · CPC title

• G02B6/02042

  Multicore optical fibres · CPC title