Diode laser apparatus with FAC lens out-of-plane beam steering

Patent metadata

Field	Value
Publication number	US-11979002-B2
Application number	US-202017093111-A
Country	US
Kind code	B2
Filing date	Nov 9, 2020
Priority date	Feb 6, 2018
Publication date	May 7, 2024
Grant date	May 7, 2024

Abstract

Apparatus include a first laser diode situated to emit a beam from an exit facet along an optical axis, the beam as emitted having perpendicular fast and slow axes perpendicular to the optical axis, a first fast axis collimator (FAC) optically coupled to the beam as emitted from the exit facet and configured to direct the beam along a redirected beam axis having a non-zero angle with respect to the optical axis of the first laser diode, a second laser diode situated to emit a beam from an exit facet of the second laser diode along an optical axis parallel to the optical axis of the first laser diode and with a slow axis in a common plane with the slow axis of the first laser diode, and a second fast axis collimator (FAC) optically coupled to the beam as emitted from the exit facet of the second laser diode and configured to direct the beam along a redirected beam axis having a non-zero angle with respect to the optical axis of the second laser diode.

First claim

We claim:

1. An apparatus, comprising:
a first laser diode situated to emit a beam along an optical axis, the beam having perpendicular fast and slow axes perpendicular to the optical axis;
a first fast axis collimator (FAC) optically coupled to the beam;
a second laser diode situated to emit a beam along an optical axis;
a second fast axis collimator (FAC) optically coupled to the beam emitted from the second laser diode; and
first and second turning mirrors situated to receive the beams and to turn the beams for stacking along the fast axes;
wherein at least one of the first or second turning mirrors has a shape defined by a departure from a rectangular parallelepiped shape, wherein the departure defines a surface and volume configured to provide clearance for the beam turned by the other of the first or second turning mirrors to propagate adjacent to the surface with at least a portion propagating through the volume.

2. The apparatus of claim 1 , wherein the surface comprises a chamfer.

3. The apparatus of claim 1 , wherein the surface comprises a bevel.

4. The apparatus of claim 3 , wherein the bevel extends to a receiving reflective surface of the at least one first or second turning mirror.

5. The apparatus of claim 1 , wherein both the first and second turning mirrors comprise respective surfaces defined by respective parallelepiped subtractions.

6. The apparatus of claim 5 , wherein the surfaces are differently shaped from each other.

7. The apparatus of claim 1 , wherein the first FAC has an optical axis arranged at a non-zero angle with respect to the optical axis of the first laser diode to produce a redirected beam axis that is redirected at an angle greater than or equal to 2 degrees and less than or equal to 20 degrees with respect to the optical axis of the first laser diode.

8. The apparatus of claim 1 , wherein the first FAC has an optical axis parallel to the optical axis of the first laser diode but spaced apart by a distance to produce a redirected beam axis.

9. A laser diode pump module comprising the apparatus of claim 1 .

10. A fiber laser system, comprising one or more of the laser diode pump modules of claim 9 .

11. A method, comprising:
arranging a plurality of laser diodes in a laser diode module to emit respective beams from emission facets along optical axes, wherein the beams as emitted have perpendicular fast and slow axes perpendicular to the respective parallel optical axis; and
securing at least one fast axis collimator (FAC) in relation to one of the emission facets, wherein the FAC is secured such that a FAC optical axis is at a non-zero angle with respect to the optical axis of the beam emitted from the one emission facet so that the beam is redirected along a redirected beam axis at an angle greater than or equal to 2 degrees and less than or equal to 20 degrees with respect to the FAC optical axis after transmission through the at least one FAC.

12. The method of claim 11 , wherein the securing the at least one FAC in relation to one of the emission facets comprises securing the at least one FAC with a UV cured epoxy, high temperature glue, or lens bonding material.

13. The method of claim 11 , wherein the securing the at least one FAC in relation to one of the emission facets comprises securing the FAC to a laser diode submount, the respective laser diode, a mounting surface of the laser diode module, and/or an intermediate securing member.

14. The method of claim 11 , wherein the securing the at least one FAC in relation to one of the emission facets comprises securing the FAC such that the FAC is in contact with a laser diode submount, a respective laser diode, a mounting surface of the laser diode module, and/or an intermediate securing member.

15. The method of claim 11 , further comprising securing another fast axis collimator (FAC) in relation to another of the emission facets, wherein the FAC is secured such that a FAC optical axis is at a non-zero angle with respect to the optical axis of the beam emitted from the other emission facet so that the beam is redirected along a redirected beam axis after transmission through the other FAC.

16. The method of claim 11 , wherein the securing the at least one FAC in relation to one of the emission facets comprises securing the FAC such that the FAC optical axis intersects the beam optical axis at the emission facet.

17. The method of claim 11 , further comprising securing one or more turning mirrors in relation to respective laser diodes to receive the beams along the respective redirected beam axes and to turn the beams to become stacked along the fast axes and to redirect the beams to propagate at a common angle.

18. The method of claim 11 , wherein the arranging the plurality of laser diodes in a laser diode module to emit respective beams from emission facets along optical axes comprises arranging the optical axes in a common plane.

19. The method of claim 18 , further comprising securing at least one wedge prisms situated to receive the beams along one of the respective redirected beam axes and configured to redirect the beams to propagate at a common angle with respect to the common plane.

20. An apparatus, comprising:
at least one laser diode configured to emit a beam from an exit facet along an optical axis, wherein the beam as emitted having perpendicular fast and slow axes perpendicular to the optical axis; and
means for collimating the beam along the fast axis while redirecting the beam at an angle with respect to the optical axis at least in part using a non-parallel optical axis relation and for producing a redirected collimated beam propagating in free space along a redirected beam axis that is at an angle greater than or equal to 2 degrees and less than or equal to 20 degrees with respect to the optical axis.

21. An apparatus, comprising:
a first laser diode situated to emit a beam along an optical axis, the beam having perpendicular fast and slow axes perpendicular to the optical axis;
a first fast axis collimator (FAC) optically coupled to the beam;
a second laser diode situated to emit a beam along an optical axis;
a second fast axis collimator (FAC) optically coupled to the beam emitted from the second laser diode; and
first and second turning mirrors situated to receive the beams and to turn the beams for stacking along the fast axes;
wherein at least one of the first or second turning mirrors has a shape defined by a departure from a rectangular parallelepiped shape, wherein the departure defines a surface configured to provide clearance for the beam turned by the other of the first or second turning mirrors to propagate adjacent to the surface;
wherein the first FAC has an optical axis arranged at a non-zero angle with respect to the optical axis of the first laser diode to produce a redirected beam axis that is redirected at an angle greater than or equal to 2 degrees and less than or equal to 20 degrees with respect to the optical axis of the first laser diode.

Assignees

• Nlight Inc

Inventors

• Chen Zhigang
• Kanskar Manoj
• Li Shuang
• Zhang Jim
• Defranza Mark
• Hemenway David Martin
• Martin Eric
• Small Jay

Classifications

• H01S5/02423

  Liquid cooling, e.g. a liquid cools a mount of the laser · CPC title

• H01S5/02208

  characterised by the shape of the housings · CPC title

• H01S5/02325

  Mechanically integrated components on mount members or optical micro-benches · CPC title

• H01S5/02251

  using optical fibres · CPC title

• H01S5/02255

  using beam deflecting elements · CPC title