Ruggedized fiber optic laser for high stress environments

Patent metadata

Field	Value
Publication number	US-9680279-B2
Application number	US-201514844417-A
Country	US
Kind code	B2
Filing date	Sep 3, 2015
Priority date	Sep 10, 2014
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

A fiber optic laser for use in high stress environments is provided. The fiber optic laser comprises a hollow spool structure housing a fiber in a spiral groove in an interior surface of said hollow spool structure, wherein the fiber is mechanically supported along an entirety of its length within the hollow spool structure. Fluid channels are formed within the hollow spool structure, wherein a quantity of coolant is movable through the fluid channels to provide high-precision thermal management of the fiber.

First claim

What is claimed is:

1. A fiber optic laser comprising:
a hollow spool structure housing a fiber in a spiral groove in an interior surface of said hollow spool structure, wherein the fiber is mechanically supported along an entirety of its length within the hollow spool structure; and
fluid channels formed within the hollow spool structure, wherein a quantity of coolant is movable through the fluid channels to provide high-precision thermal management of the fiber,
wherein said hollow spool structure includes an integral flat surface adapted to carry a passive optical fiber and for routing said passive optical fiber around a spool core and back to the spool core at a proximal end of an active doped fiber, wherein a plane at which the passive optical fiber meets the proximal end is tangential to a plane of the active doped fiber at the proximal end.

2. The fiber optic laser of claim 1 , wherein the hollow spool structure has an axis and wherein the fluid channels are positioned axially with respect to the axis of the spool.

3. The fiber optic laser claim 2 , wherein the fluid channels surround an apertured core of the hollow spool structure.

4. The fiber optic laser of claim 1 , further comprising a plurality of hollow spool structures, each having fluid channels therein, wherein the plurality of hollow spool structures are stacked one on top of the other.

5. The fiber optic laser of claim 4 , wherein the fluid channels in each of the hollow spool structures are aligned, wherein the fluid channels in each of the hollow spool structure are axially aligned.

6. The fiber optic laser of claim 5 , further comprising gasket structures positioned between the stack of the plurality of hollow spool structures, wherein a seal is created between each of the plurality of hollow spool structures.

7. The fiber optic laser of claim 4 , further comprising a thermal insulating material positioned between each of the hollow spool structures.

8. The fiber optic laser of claim 1 , wherein the passive optical fiber is clamped at a strain relief assembly to the hollow spool structure on the plane both at an input and an output of the hollow spool structure.

9. The fiber optic laser of claim 8 , wherein the strain relief assembly includes staggered flat recesses positioned to accommodate portions of the passive optical fiber.

10. The fiber optic laser of claim 9 , wherein the portions of the passive optical fiber include: flexible metal jacketing, an internal strain relief boot, polymer jacketing, and an optical fiber core.

11. The fiber optic laser of claim 1 , further comprising a passive fiber adapted to be coupled to an active doped fiber at a splice, wherein the splice includes staggered flat recesses to accommodate portions of the active and passive optical fibers, wherein ends of fibers to be spliced are in axial alignment with one another.

12. The fiber optic laser of claim 1 , further comprising an encapsulant encapsulating the fiber in the grooves.

13. The fiber optic laser of claim 12 , wherein said encapsulant includes thermally conductive material.

14. A fiber optic laser assembly comprising:
a plurality of stacked spool lasers, each of the stacked spools having a hollow spool core;
a grooved spiral structure formed on an inner surface of the hollow spool core of each of the plurality of stacked spool lasers;
an active doped fiber positioned at least partially within the grooved structure, wherein the active doped fiber is continuously supported within the fiber optic laser assembly; and
cooling channels running through the plurality of stacked spool lasers, wherein the cooling channels carry heat away from the active doped fiber in the grooved spiral structure; wherein the cooling channels run axially through the plurality of stacked spool lasers, wherein the cooling channels are axially aligned with each other to provide an axial cooling channel up through each of the plurality of stacked spool lasers, wherein each of the stacked spool lasers has:
a pair of fiber Bragg gratings at either end of the active doped fiber; and
temperature control assemblies at each of the fiber Bragg gratings to control the temperature thereof.

15. The fiber optic laser assembly of claim 14 , wherein control of the temperature of said fiber Bragg gratings and that of the active doped fiber controls the spectral output of each of the plurality of stacked spool lasers.

Assignees

• Bae Sys Inf & Elect Sys Integ

Inventors

• Johnson Benjamin R
• Shaw Michael J
• Forbes Tyler

Classifications

• H01S3/094003

  the pumped medium being a fibre · CPC title

• H01S3/09415

  the pumping beam being parallel to the lasing mode of the pumped medium, e.g. end-pumping · CPC title

• H01S3/0675

  Resonators including a grating structure, e.g. distributed Bragg reflectors [DBR] or distributed feedback [DFB] fibre lasers · CPC title

• H01S3/042

  for solid state lasers {(H01S3/0401 takes precedence)} · CPC title

• G02B6/4457

  Bobbins; Reels · CPC title