Wavelength beam combining laser systems with micro-optics
View Patent ↗In various embodiments, wavelength beam combining systems feature multiple beam emitters each emitting an individual beam, as well as multiple micro-optics arrangements each disposed optically downstream from a beam emitter to intercept the beam emitted thereby and direct the beam toward a dispersive element for combination into a multi-wavelength output beam.
1. A laser system comprising:
a plurality of beam emitters each emitting an individual beam;
a plurality of micro-optics arrangements, each micro-optic arrangement being disposed optically downstream from a beam emitter to (i) intercept only the beam emitted thereby, (ii) rotate the beam, and (iii) direct the beam toward a dispersive element;
disposed optically downstream from the plurality of micro-optics arrangements, focusing optics for overlapping the rotated beams on the dispersive element, the focusing optics having a focal length;
a dispersive element for receiving and dispersing the overlapped rotated beams; and
a partially reflective output coupler for receiving the dispersed beams, reflecting a first portion thereof back toward the dispersive element, and transmitting a second portion thereof as a multi-wavelength output beam,
wherein (i) an optical distance between the focusing optics and the dispersive element is less than the focal length, and (ii) each micro-optics arrangement rotates its corresponding beam by a different angle to thereby converge the beams toward each other before the beams reach the focusing optics.
2. The laser system of claim 1 , wherein each micro-optics arrangement is disposed proximate a front facet of the beam emitter emitting the beam intercepted by the micro-optics arrangement.
3. The laser system of claim 1 , wherein the dispersive element comprises a diffraction grating.
4. The laser system of claim 1 , wherein the focusing optics comprises a spherical lens.
5. The laser system of claim 1 , wherein an optical distance between the plurality of beam emitters and the focusing optics is approximately equal to the focal length.
6. The laser system of claim 1 , wherein each micro-optics arrangement comprises a fast-axis collimation lens, an optical rotator, and a slow-axis collimation lens.
7. The laser system of claim 6 , wherein the optical rotator is disposed (i) optically downstream from the fast-axis collimation lens and (ii) optically upstream from the slow-axis collimation lens.
8. The laser system of claim 1 , further comprising a cross-talk mitigation system disposed (i) optically downstream from the dispersive element and (ii) optically upstream from the partially reflective output coupler.
9. The laser system of claim 8 , wherein the cross-talk mitigation system comprises a plurality of spherical lenses.
10. The laser system of claim 8 , wherein the cross-talk mitigation system comprises (i) a first lens having a first focal length, and (ii) a second lens, disposed optically downstream from the first lens, having a second focal length.
11. The laser system of claim 10 , wherein a ratio of the first focal length to the second focal length is two or greater.
12. The laser system of claim 10 , wherein an optical distance between the first and second lenses is approximately equal to a sum of the first and second focal lengths.
13. A laser system comprising:
a plurality of beam emitters each emitting an individual beam;
a plurality of micro-optics arrangements, each micro-optic arrangement (i) being disposed optically downstream from a beam emitter to (a) intercept only the beam emitted thereby, and (b) direct the beam toward a dispersive element, and (ii) comprising a fast-axis collimation lens, an optical rotator optically downstream of the fast-axis collimation lens, and a slow-axis collimation lens optically downstream of the optical rotator;
disposed optically downstream from the plurality of micro-optics arrangements, focusing optics for overlapping the beams on the dispersive element, the focusing optics having a focal length;
a dispersive element for receiving and dispersing the overlapped beams;
a partially reflective output coupler for receiving the dispersed beams, reflecting a first portion thereof back toward the dispersive element, and transmitting a second portion thereof as a multi-wavelength output beam; and
a cross-talk mitigation system disposed (i) optically downstream from the dispersive element and (ii) optically upstream from the partially reflective output coupler.
14. The laser system of claim 13 , wherein an optical distance between the focusing optics and the dispersive element is less than the focal length.
15. The laser system of claim 13 , wherein each micro-optics arrangement is disposed proximate a front facet of the beam emitter emitting the beam intercepted by the micro-optics arrangement.
16. The laser system of claim 13 , wherein the dispersive element comprises a diffraction grating.
17. The laser system of claim 13 , wherein the focusing optics comprises a spherical lens.
18. The laser system of claim 13 , wherein an optical distance between the plurality of beam emitters and the focusing optics is approximately equal to the focal length.
19. The laser system of claim 13 , wherein the cross-talk mitigation system comprises a plurality of spherical lenses.
20. The laser system of claim 13 , wherein the cross-talk mitigation system comprises (i) a first lens having a first focal length, and (ii) a second lens, disposed optically downstream from the first lens, having a second focal length.
21. The laser system of claim 20 , wherein a ratio of the first focal length to the second focal length is two or greater.
22. The laser system of claim 20 , wherein an optical distance between the first and second lenses is approximately equal to a sum of the first and second focal lengths.