Wavelength beam combining laser systems with high beam quality factor
In various embodiments, optical repositioners and/or angled dispersive elements are utilized to manipulate portions of an input laser beam emitted by a group of laser emitters in order to form a multi-wavelength output beam having a high beam quality factor.
1. A method for forming an output laser beam, the method comprising:
propagating an input beam toward a dispersive element;
intercepting and redirecting one or more first portions of the input beam upstream of the dispersive element while allowing a second portion of the input beam to propagate to the dispersive element without being intercepted and redirected;
causing the one or more first portions of the input beam to at least partially overlap with the second portion of the input beam at the dispersive element, whereby a dispersed beam is formed; and
transmitting a first portion of the dispersed beam as an output beam.
2. The method of claim 1 , further comprising forming an external lasing cavity with a second portion of the dispersed beam.
3. The method of claim 2 , wherein forming the external lasing cavity comprises reflecting the second portion of the dispersed beam back to the dispersive element and thence to a beam source.
4. The method of claim 1 , further comprising forming the input beam by:
emitting a plurality of beams from a beam source; and
focusing the beams to form the input beam.
5. The method of claim 4 , wherein the beam source comprises one or more beam emitters.
6. The method of claim 1 , wherein intercepting and redirecting one or more first portions of the input beam comprises intercepting and redirecting a plurality of first portions of the input beam.
7. The method of claim 6 , wherein each first portion of the input beam comprises approximately one-third of the input beam.
8. The method of claim 1 , wherein the second portion of the input beam comprises approximately one-third of the input beam.
9. The method of claim 1 , wherein each first portion of the input beam is intercepted and redirected by at least one of a reflector or an optical element.
10. The method of claim 1 , wherein the dispersive element comprises a diffraction grating.
11. The method of claim 1 , wherein the first portion of the dispersed beam is transmitted by a partially reflective output coupler.
12. The method of claim 1 , further comprising directing the first portion of the dispersed beam to a workpiece.
13. The method of claim 12 , further comprising processing the workpiece with the first portion of the dispersed beam.
14. The method of claim 13 , wherein processing the workpiece comprises at least one of welding, cutting, or drilling.
15. The method of claim 1 , further comprising coupling the first portion of the dispersed beam into an optical fiber.
16. A method for forming an output laser beam, the method comprising:
propagating an input beam toward a dispersive element, the input beam having first and second orthogonal dimensions;
focusing the input beam in the first dimension;
upstream of the dispersive element and downstream of the focusing in the first dimension, reducing a size of the input beam in the second dimension;
forming a dispersed beam from the input beam at the dispersive element; and
transmitting a first portion of the dispersed beam as an output beam.
17. The method of claim 16 , wherein reducing the size of the input beam comprises at least partially overlapping, in the second dimension, one or more first portions of the input beam with a second portion of the input beam.
18. The method of claim 16 , further comprising forming an external lasing cavity with a second portion of the dispersed beam.
19. The method of claim 18 , wherein forming the external lasing cavity comprises reflecting the second portion of the dispersed beam back to the dispersive element and thence to a beam source.
20. The method of claim 16 , wherein the input beam comprises beams emitted by a plurality of beam emitters.