Packages for high-power laser devices
In various embodiments, a laser emitter such as a diode bar is cooled during operation via jets of cooling fluid formed by ports in a cooler on which the laser emitter is positioned. The jets strike an impingement surface of the cooler that is thermally coupled to the laser emitter but prevents direct contact between the cooling fluid and the laser emitter itself.
1. A laser package comprising:
a bottom anode cooler having (i) a top surface, (ii) a bottom surface opposite the top surface, (iii) an entry recess defined in the bottom surface, (iv) a top recess defined in the top surface, and (v) fluidly connecting the entry recess and the top recess, a plurality of hollow ports for forming jets of cooling fluid therethrough, wherein the top surface of the bottom anode cooler comprises (a) a first portion surrounding the top recess, (b) a second portion, coplanar with the first portion, extending to a rear side of the bottom anode cooler, and (c) a front depression extending from the first portion to a front side of the bottom anode cooler and recessed below the first and second portions; and
disposed above the bottom anode cooler, a top anode cooler having (i) a top surface and (ii) a bottom surface opposite the top surface, the bottom surface comprising an impingement surface and a planar outer border surrounding the impingement surface, wherein (a) the outer border is coupled to the first portion of the bottom anode cooler, and (b) the top anode cooler does not overlie the second portion of the top surface of the bottom anode cooler or the front depression,
wherein (i) the impingement surface defines a non-planar pattern protruding into the top recess of the bottom anode cooler, whereby cooling fluid introduced into the bottom anode cooler and jetted through the ports strikes the impingement surface of the top anode cooler to cool a laser emitter when the laser emitter is disposed on the top surface of the top anode cooler, and (ii) the front depression of the bottom anode cooler accommodates one or more laser beams emitted by the laser emitter when the laser emitter is disposed on the top surface of the top anode cooler.
2. The laser package of claim 1 , wherein at least a portion of at least one of the bottom anode cooler or the top anode cooler comprises at least one of copper, aluminum, stainless steel, CuW, tungsten, WC, alumina, mullite, diamond, or SiC.
3. The laser package of claim 1 , wherein the non-planar pattern comprises a plurality of raised features.
4. The laser package of claim 1 , wherein the bottom anode cooler defines a plurality of raised struts disposed between openings of the ports.
5. The laser package of claim 1 , further comprising a cathode cooler (i) disposed over the top anode cooler, wherein a portion of the cathode cooler overhangs and does not contact the top surface of the top anode cooler.
6. The laser package of claim 5 , wherein the cathode cooler is not configured for the flow of cooling fluid therethrough.
7. The laser package of claim 1 , wherein the top anode cooler is not configured for the flow of cooling fluid therethrough.
8. The laser package of claim 1 , wherein the non-planar pattern is spaced away from openings of the ports to form a mixing channel for the cooling fluid.
9. The laser package of claim 8 , wherein the mixing channel has a height selected from the range of approximately 0.025 mm to approximately 50 mm.
10. The laser package of claim 8 , wherein a ratio of the height of the mixing channel to a diameter of at least one of the ports is selected from the range of approximately 0.1 to approximately 30.
11. The laser package of claim 8 , wherein a ratio of the height of the mixing channel to a diameter of at least one of the ports is selected from the range of approximately 8 to approximately 30.
12. The laser package of claim 8 , wherein a ratio of the height of the mixing channel to a diameter of at least one of the ports is selected from the range of approximately 0.1 to approximately 2.
13. The laser package of claim 1 , wherein a center-to-center spacing of the ports is selected from the range of approximately 0.1 mm to approximately 8 mm.
14. The laser package of claim 1 , wherein a diameter of at least one of the ports is selected from the range of approximately 0.025 mm to approximately 5 mm.
15. The laser package of claim 1 , wherein a surface area of an entirety of the top surface of the top anode cooler is smaller than a surface area of an entirety of the second portion of the top surface of the bottom anode cooler.
16. The laser package of claim 1 , wherein the bottom anode cooler defines therewithin an exit channel fluidly connecting the top recess with an exit aperture defined in the bottom surface of the bottom anode cooler and spaced away from the entry recess.
17. The laser package of claim 16 , wherein an entire portion of the bottom surface of the bottom anode cooler extending between the entry recess and the exit aperture is planar and parallel to the second portion of the top surface of the bottom anode cooler.
18. The laser package of claim 1 , further comprising an attachment material attaching the outer border of the bottom surface of the top anode cooler to the first portion of the top surface of the bottom anode cooler.
19. The laser package of claim 18 , wherein the attachment material comprises at least one of an adhesive, solder, or a brazing material.
20. The laser package of claim 1 , wherein the bottom anode cooler comprises alumina and the top anode cooler comprises SiC.
21. The laser package of claim 1 , further comprising the laser emitter disposed on the top surface of the top anode cooler, the laser emitter comprising a laser diode bar configured to emit a plurality of beams in a direction toward the front depression.
22. The laser package of claim 1 , wherein the front depression is recessed below the first portion of the top surface of the bottom anode cooler by approximately 0.025 mm to approximately 50 mm.
23. The laser package of claim 1 , wherein both the top anode cooler and the bottom anode cooler are electrically insulating.