Radiation-induced birefringence in Polarization-Maintaining Fiber

Patent metadata

Field	Value
Publication number	US-12072525-B2
Application number	US-202318295360-A
Country	US
Kind code	B2
Filing date	Apr 4, 2023
Priority date	Sep 9, 2021
Publication date	Aug 27, 2024
Grant date	Aug 27, 2024

Abstract

Techniques are provided for radiation-induced birefringence in a Polarization-Maintaining Fiber (PMF). In one example, a fiber is obtained. At least one local volume of the fiber is irradiated to induce an end-to-end birefringence in the fiber. Based on the end-to-end birefringence induced in the fiber, a PMF is produced.

First claim

What is claimed is:

1. A method comprising:
obtaining a blank fiber;
irradiating at least one local volume of the blank fiber to induce an end-to-end birefringence in the blank fiber;
automatically adjusting the blank fiber or the irradiating of the at least one local volume of the blank fiber based on the end-to-end birefringence induced in the blank fiber; and
based on the end-to-end birefringence induced in the blank fiber, producing a polarization-maintaining fiber.

2. The method of claim 1 , wherein irradiating the at least one local volume of the blank fiber includes:
altering a matrix structure of the blank fiber at the at least one local volume of the blank fiber.

3. The method of claim 1 , wherein irradiating the at least one local volume of the blank fiber includes:
irradiating the at least one local volume of the blank fiber using a femtosecond laser.

4. The method of claim 1 , wherein the blank fiber is part of a ribbon of fibers.

5. The method of claim 4 , wherein the irradiating of the at least one local volume of the blank fiber comprises irradiating at least one local volume of each of the ribbon of fibers to induce the end-to-end birefringence in each of the ribbon of fibers, and the method further comprising:
based on the end-to-end birefringence induced in each of the ribbon of fibers, producing a ribbon of polarization-maintaining fibers including the polarization-maintaining fiber.

6. The method of claim 4 , further comprising:
producing a hybrid ribbon that includes the polarization-maintaining fiber and at least one fiber in which the end-to-end birefringence has not been induced.

7. The method of claim 4 , wherein irradiating the at least one local volume of the blank fiber includes:
orienting a fast axis and a slow axis at angles that are configurable relative to the ribbon of fibers.

8. The method of claim 1 , wherein irradiating the at least one local volume of the blank fiber includes:
irradiating at least one continuous local volume over a substantially end-to-end length of the blank fiber.

9. The method of claim 1 , wherein irradiating the at least one local volume of the blank fiber includes:
irradiating a plurality of discontinuous local volumes over a substantially end-to-end length of the blank fiber.

10. The method of claim 1 , further comprising:
automatically obtaining feedback regarding the end-to-end birefringence induced in the blank fiber; and
based on the feedback, automatically adjusting one or more parameters that control the irradiating of the at least one local volume of the blank fiber to automatically adjust the blank fiber or the irradiating of the at least one local volume of the blank fiber and induce the end-to-end birefringence in the blank fiber.

11. The method of claim 10 , wherein:
automatically obtaining the feedback includes automatically obtaining positioning data of the blank fiber; and
automatically adjusting the one or more parameters includes, based on the positioning data of the blank fiber, automatically adjusting the blank fiber or a radiation source used to irradiate the at least one local volume of the blank fiber.

12. An apparatus comprising:
a polarization-maintaining fiber that includes at least one continuous local volume that has been irradiated over a substantially end-to-end length of the polarization-maintaining fiber to induce an end-to-end birefringence in the polarization-maintaining fiber, wherein the polarization-maintaining fiber or irradiation of the at least one continuous local volume of the polarization-maintaining fiber has been adjusted based on the end-to-end birefringence induced in the polarization-maintaining fiber.

13. The apparatus of claim 12 , further comprising:
a ribbon of fibers including the polarization-maintaining fiber.

14. The apparatus of claim 12 , wherein the at least one continuous local volume includes an altered matrix structure.

15. An apparatus comprising:
a radiation source; and
one or more processors configured to control the radiation source to irradiate at least one local volume of a fiber to induce an end-to-end birefringence in the fiber to produce a polarization-maintaining fiber by:
automatically obtaining positioning data of the fiber regarding the end-to-end birefringence induced in the fiber; and
automatically adjusting the fiber or the radiation source based on the positioning data.

16. The apparatus of claim 15 , wherein the radiation source includes a femtosecond laser.

17. A method comprising:
obtaining a multi-core fiber;
irradiating at least one local volume of the multi-core fiber to induce an end-to-end birefringence in the multi-core fiber;
automatically adjusting the multi-core fiber or the irradiating of the at least one local volume of the multi-core fiber based on the end-to-end birefringence induced in the multi-core fiber; and
based on the end-to-end birefringence induced in the multi-core fiber, producing a polarization-maintaining fiber.

18. The method of claim 17 , wherein irradiating the at least one local volume of the multi-core fiber includes:
irradiating at least one continuous local volume over a substantially end-to-end length of the multi-core fiber.

19. The method of claim 17 , comprising:
automatically obtaining positioning data of the multi-core fiber regarding the end-to-end birefringence induced in the multi-core fiber; and
automatically adjusting the multi-core fiber or a radiation source used to irradiate the at least one local volume of the multi-core fiber based on the positioning data of the multi-core fiber.

20. The method of claim 17 , wherein the multi-core fiber is part of a ribbon of fibers.

Assignees

• Cisco Tech Inc

Inventors

• Schlepple Norbert

Classifications

• G02B6/024 Primary

  with polarisation maintaining properties · CPC title