Apparatus, system and method for compact active fiber packaging of a fiber laser

1 . A compact fiber packaging apparatus configured to guide an active fiber as part of a high-power fiber laser, the apparatus comprising:

a base having a front side, a back side, and

an outer base surface extending between outer rims of the front side and the back side;

wherein the front side comprises a front spiral groove of varying radii increasingly extending from an innermost front loop having an innermost radius to an outermost front loop having an outermost radius;

wherein the back side comprises a back spiral groove of varying radii decreasingly extending from an outermost back loop having an outermost radius to an innermost back loop having an innermost radius;

wherein the innermost radius is smaller than the outermost radius; and

wherein the front spiral groove extends from the innermost front loop to the outermost front loop, and wherein the outermost front loop is configured to operably connect, via the outer base surface, with the outermost back loop of the back spiral groove to terminate at the innermost back loop such to eliminate or prevent thermal mode instability (TMI) of the active fiber, while avoiding overbending of the active fiber;

wherein the base includes fluid conduits which enable cooled fluid to flow through them for cooling of the active fiber.

2 . The apparatus of claim 1 , wherein the outermost front loop connects with the outermost back loop of the back spiral groove over an external surface of the base.

3 . The apparatus of claim 2 , wherein the innermost front loop terminates in a front input section configured for splicing an input fiber with the input section and/or the innermost back loop terminates in a back output section configured for splicing of an output fiber with the output section.

4 . The apparatus of claim 3 , wherein the input section extends distally into the base underneath the front spiral groove; and

wherein the output section extends distally into the base underneath or above the back spiral groove.

5 . The apparatus of claim 4 , wherein the front input section and/or the back output section are straight linear sections.

6 . The apparatus of claim 5 , wherein the front loops and/or the back loops are coplanar.

7 . The apparatus of claim 1 , wherein the front spiral groove comprises front loops; and wherein the back spiral groove comprises back loops to allow accommodation of corresponding portions of the active fiber.

8 . The apparatus of claim 1 , wherein the base comprises one or more fluid conduits that are arranged within the base between the front spiral groove and the back spiral groove,

the one or more fluid conduits being configured to allow flow of a cooling fluid for cooling the active fiber accommodatable in the front spiral groove and the back spiral groove by thermal conduction.

9 . The apparatus of claim 8 , wherein a plurality of the one or more fluid conduits is arranged to delineate coplanar loops.

10 . The apparatus of claim 9 , wherein one or more fluid conduits have at least one fluid inlet and fluid outlet.

11 . The apparatus of claim 8 , wherein the one or more fluid conduits have at least one fluid inlet and fluid outlet.

12 . The apparatus of claim 1 , further comprising a fastener for securing the active fiber within the front and the back spiral groove.

13 . The apparatus of claim 12 , wherein the fastener includes an adhesive and/or potting material.

14 . The apparatus of claim 1 , wherein the active fiber may be part of an oscillator-based laser or an amplifier-based laser.

15 . A method for guiding an active fiber by providing a compact fiber packaging apparatus according to claim 1 .

16 . A cooling system for cooling a compact fiber packaging apparatus configured to guide an active fiber as part of a high-power fiber laser, the apparatus comprising a base having a front side,

a back side,

an outer base surface extending between outer rims of the front side and the back side;

wherein the front side of the compact fiber packaging apparatus comprises a front spiral groove of varying radii increasingly extending from an innermost front loop having an innermost radius to an outermost front loop having an outermost radius;

wherein the back side comprises a back spiral groove of varying radii decreasingly extending from an outermost back loop having an outermost radius to an innermost back loop having an innermost radius;

wherein the outermost front loop is configured to operably connect, via the outer base surface with the outermost back loop of the back spiral groove to terminate at the innermost back loop such to eliminate or prevent thermal mode instability (TMI) of the active fiber while avoiding overbending of the active fiber;

and

wherein the cooling system comprises:

one or more fluid conduits that are arranged within the base between the front spiral groove and the back spiral groove, wherein the one or more fluid conduits being configured to allow flow of a cooling fluid for cooling an active fiber accommodatable in the front spiral groove and the back spiral groove by thermal conduction;

a heat exchanger and/or chiller for cooling inlet fluid to generate cooling fluid; and

a pump device configured to impart energy onto the cooling fluid to cause flow of the cooling fluid through the one or more fluid conduits.

17 . The cooling system of claim 16 , wherein plurality of the one or more fluid conduits is arranged to delineate coplanar loops.

18 . The cooling system of claim 16 , wherein the one or more fluid conduits have at least one fluid inlet and fluid outlet.

19 . The cooling system of claim 17 , wherein the one or more fluid conduits have at least one fluid inlet and fluid outlet.

20 . A method for cooling a compact fiber packaging apparatus according to claim 16 .