INTEGRATED WAVELENGTH BEAM COMBINING LASER SYSTEMS
In various embodiments, an integrated laser apparatus includes a substrate, portions of which define a plurality of input waveguides, a dispersive element, and an output waveguide, an output facet of the output waveguide being partially reflective so as to transmit a multi-wavelength output beam.
1 . An integrated laser apparatus comprising:
an array of beam emitters each emitting an input beam; and
a glass substrate optically coupled to the array of beam emitters, portions of the substrate defining:
(i) a plurality of input waveguides for receiving the input beams from the array of beam emitters and propagating the beams over the substrate,
(ii) focusing optics for receiving the beams from the input waveguides and converging the received beams toward a dispersive element,
(iii) a dispersive element for receiving the converged beams and dispersing the converged beams, thereby forming a dispersed beam, and
(iv) an output waveguide for receiving the dispersed beam from the dispersive element, an output facet of the output waveguide (a) comprising a portion of an exterior surface of the substrate, and (b) forming a partially reflective output coupler that (A) transmits a first portion of the dispersed beam as a multi-wavelength output beam and (B) reflects a second portion of the dispersed beam back toward the dispersive element and the array of beam emitters, thereby forming an external cavity that stabilizes each of the input beams at a different wavelength.
2 . The integrated laser apparatus of claim 1 , wherein the substrate comprises fused silica or quartz.
3 . The integrated laser apparatus of claim 1 , wherein an OH content of the substrate is less than 5 ppm.
4 . The integrated laser apparatus of claim 1 , wherein a concentration of metallic impurities in the substrate is less than 5 ppm.
5 . The integrated laser apparatus of claim 1 , further comprising a partially reflective coating disposed on the output facet of the output waveguide.
6 . The integrated laser apparatus of claim 1 , wherein the array of beam emitters is butt-coupled to the substrate.
7 . The integrated laser apparatus of claim 6 , further comprising an index-matching material disposed between the array of beam emitters and the substrate.
8 . The integrated laser apparatus of claim 1 , wherein an input facet of each of the input waveguides comprises a portion of an exterior surface of the substrate.
9 . The integrated laser apparatus of claim 8 , further comprising an anti-reflection coating on the input facet of each of the input waveguides.
10 . An integrated laser apparatus comprising:
an array of beam emitters each emitting an input beam; and
a glass substrate optically coupled to the array of beam emitters, portions of the substrate defining:
(i) a plurality of input waveguides for receiving the input beams from the array of beam emitters and propagating the beams over the substrate, wherein at least portions of the input waveguides are mutually angled and/or curved to overlap the input beams at a point proximate a dispersive element,
(ii) a dispersive element for receiving the overlapped beams and dispersing the overlapped beams, thereby forming a dispersed beam, and
(iii) an output waveguide for receiving the dispersed beam from the dispersive element, an output facet of the output waveguide (a) comprising a portion of an exterior surface of the substrate, and (b) forming a partially reflective output coupler that (A) transmits a first portion of the dispersed beam as a multi-wavelength output beam and (B) reflects a second portion of the dispersed beam back toward the dispersive element and the array of beam emitters, thereby forming an external cavity that stabilizes each of the input beams at a different wavelength.
11 . The integrated laser apparatus of claim 10 , wherein an optical path between the input waveguides and the dispersive element is free of focusing optics.
12 . The integrated laser apparatus of claim 10 , wherein the substrate comprises fused silica or quartz.
13 . The integrated laser apparatus of claim 10 , wherein an OH content of the substrate is less than 5 ppm.
14 . The integrated laser apparatus of claim 10 , wherein a concentration of metallic impurities in the substrate is less than 5 ppm.
15 . The integrated laser apparatus of claim 10 , further comprising a partially reflective coating disposed on the output facet of the output waveguide.
16 . The integrated laser apparatus of claim 10 , wherein the array of beam emitters is butt-coupled to the substrate.
17 . The integrated laser apparatus of claim 16 , further comprising an index-matching material disposed between the array of beam emitters and the substrate.
18 . The integrated laser apparatus of claim 10 , wherein an input facet of each of the input waveguides comprises a portion of an exterior surface of the substrate.
19 . The integrated laser apparatus of claim 18 , further comprising an anti-reflection coating on the input facet of each of the input waveguides.
20 . An apparatus for producing a multi-wavelength output beam from beams emitted by an array of beam emitters, the apparatus comprising a glass substrate, portions of the substrate defining:
(i) a plurality of input waveguides for receiving the input beams from the array of beam emitters and propagating the beams over the substrate,
(ii) focusing optics for receiving the beams from the input waveguides and converging the received beams toward a dispersive element,
(iii) a dispersive element for receiving the converged beams and dispersing the converged beams, thereby forming a dispersed beam, and
(iv) an output waveguide for receiving the dispersed beam from the dispersive element, an output facet of the output waveguide (a) comprising a portion of an exterior surface of the substrate, and (b) forming a partially reflective output coupler that (A) transmits a first portion of the dispersed beam as a multi-wavelength output beam and (B) reflects a second portion of the dispersed beam back toward the dispersive element and the array of beam emitters, thereby forming an external cavity that stabilizes each of the input beams at a different wavelength.
21 . An apparatus for producing a multi-wavelength output beam from beams emitted by an array of beam emitters, the apparatus comprising a glass substrate, portions of the substrate defining:
(i) a plurality of input waveguides for receiving the input beams from the array of beam emitters and propagating the beams over the substrate, wherein at least portions of the input waveguides are mutually angled and/or curved to overlap the input beams at a point proximate a dispersive element,
(ii) a dispersive element for receiving the overlapped beams and dispersing the overlapped beams, thereby forming a dispersed beam, and
(iii) an output waveguide for receiving the dispersed beam from the dispersive element, an output facet of the output waveguide (a) comprising a portion of an exterior surface of the substrate, and (b) forming a partially reflective output coupler that (A) transmits a first portion of the dispersed beam as a multi-wavelength output beam and (B) reflects a second portion of the dispersed beam back toward the dispersive element and the array of beam emitters, thereby forming an external cavity that stabilizes each of the input beams at a different wavelength.