Cladding light stripper

Patent metadata

Field	Value
Publication number	US-10802209-B2
Application number	US-201715687052-A
Country	US
Kind code	B2
Filing date	Aug 25, 2017
Priority date	Jan 28, 2013
Publication date	Oct 13, 2020
Grant date	Oct 13, 2020

Abstract

A cladding light stripper may include a double-clad optical fiber having a core for guiding signal light, an inner cladding surrounding the core, and an outer cladding surrounding the inner cladding. The optical fiber may include a stripped portion forming an exposed section. The exposed section may include a plurality of spirally-arranged transversal notches disposed along the optical fiber to enable light to escape the inner cladding upon impinging on the plurality of notches. A circumferential segment of the optical fiber may include a single notch of the plurality of notches. Each of the plurality of notches may have a depth of only a partial distance to the core.

First claim

What is claimed is:

1. A cladding light stripper, comprising:
an optical fiber having a core for guiding signal light and a cladding surrounding the core,
the cladding including a set of notches;
each notch in the set of notches having a depth into the cladding of only a partial distance to the core; and
notches, in the set of notches, being disposed relative to each other longitudinally along the optical fiber and angularly around the core to enable light to escape the cladding upon impinging on a notch.

2. The cladding light stripper of claim 1 , wherein the notches, in the set of notches, are associated with a depth toward the core of the optical fiber of between 5% and 20% of a diameter of the optical fiber.

3. The cladding light stripper of claim 1 , wherein a pitch for adjacent notches in the set of notches, is between 400 micrometers and 1800 micrometers.

4. The cladding light stripper of claim 1 , where the optical fiber is a double-clad optical fiber.

5. The cladding light stripper of claim 1 , where the cladding includes three or more cladding layers.

6. The cladding light stripper of claim 1 , where the notches, in the set of notches, are spirally-arranged.

7. The cladding light stripper of claim 1 , where the notches, in the set of notches, are angularly displaced in a repeating pattern of angular displacements.

8. The cladding light stripper of claim 1 , where at least one notch, in the set of notches, extends from a first position at an interface of the cladding and a coating layer through the cladding to a second position at the interface of cladding and the coating layer.

9. The cladding light stripper of claim 1 , where the set of notches includes at least one spirally arranged notch extending circumferentially around the optical fiber and longitudinally from a first longitudinal position to a second longitudinal position.

10. The cladding light stripper of claim 1 , where the set of notches is arranged in a first spiral pattern; and
further comprising another set of notches arranged in a second spiral pattern,
notches of the first spiral pattern being displaced relative to notches of the second spiral pattern.

11. A cladding light stripper, comprising:
a double-clad optical fiber having a core for guiding signal light, an inner cladding surrounding the core, and an outer cladding surrounding the inner cladding,
the double-clad optical fiber including a stripped portion where the outer cladding is removed forming an exposed section of the inner cladding having a depth of only a partial distance to the core to enable light to escape the double-clad optical fiber upon impinging on at least one of a plurality of notches; and
a notch, of the plurality of notches, being disposed such that another notch of the plurality of notches, immediately preceding the notch longitudinally along the optical fiber or immediately succeeding the notch longitudinally along the double-clad optical fiber, is displaced angularly around the core relative to the notch.

12. The cladding light stripper of claim 11 , wherein a cross-section of at least one notch, of the plurality of notches, is at least one of:
a straight line,
a curved line,
an angled line, or
an irregular line.

13. The cladding light stripper of claim 11 , wherein the notch extends around an entirety of a circumference of the cladding light stripper.

14. The cladding light stripper of claim 11 , wherein the plurality of notches are spirally arranged.

15. The cladding light stripper of claim 11 , wherein the stripped portion is laser stripped.

16. The cladding light stripper of claim 11 , wherein each notch, of the plurality of notches, is formed sequentially with regard to longitudinal position.

17. The cladding light stripper of claim 11 , wherein notches, within a set of notches with a common angular position, of a plurality of sets of notches, of the plurality of notches, are formed sequentially with regard to longitudinal position; and
wherein each set of notches, of the plurality of sets of notches, is formed sequentially.

18. A cladding light stripper, comprising:
a double-clad optical fiber having a core for guiding signal light, an inner cladding surrounding the core, and an outer cladding surrounding the inner cladding,
wherein the double-clad optical fiber includes a stripped portion forming an exposed section,
wherein the exposed section includes a plurality of spirally-arranged transversal notches disposed along the double-clad optical fiber to enable light to escape the inner cladding upon impinging on the plurality of spirally-arranged transversal notches,
wherein the plurality of spirally-arranged transversal notches are disposed relative to each other longitudinally along the double-clad optical fiber and angularly around the core,
wherein a circumferential segment of the double-clad optical fiber includes a single notch of the plurality of spirally-arranged transversal notches, and
wherein each of the plurality of spirally-arranged transversal notches has a depth of only a partial distance to the core.

19. The cladding light stripper of claim 18 , wherein a first notch, of the plurality of spirally-arranged transversal notches, overlaps with a second notch, of the plurality of spirally-arranged transversal notches and immediately succeeding the first notch, with regard to an angular position around the core and on the cladding light stripper.

20. The cladding light stripper of claim 18 , wherein the partial distance to the core is between 5% and 20% of a diameter of the double-clad optical fiber.

Assignees

• Lumentum Operations Llc

Inventors

• Wu Zong Kwei
• CHONG Kwang
• Muendel Martin H

Classifications

• G02B6/264

  with optical elements between opposed fibre ends which perform a function other than beam splitting (having lens focusing means G02B6/32; utilising prism or grating G02B6/34) · CPC title

• H01S3/06733

  Fibre having more than one cladding · CPC title

• H01S3/06729

  Peculiar transverse fibre profile · CPC title

• H01S3/094007

  Cladding pumping, i.e. pump light propagating in a clad surrounding the active core · CPC title

• G02B6/02066 Primary

  Gratings having a surface relief structure, e.g. repetitive variation in diameter of core or cladding · CPC title