Low stress optics mount using thermally conductive liquid metal or gel

Abstract

An optical assembly with mounting provided to effectively transfer heat away from an optic, such as a slab or waveguide amplifier or laser disk, while limiting internal stresses. The assembly includes an optic with a planar surface. A heat sink is positioned in the assembly with an upper surface next to the planar surface of the optic. The upper surface of the heat sink comprises a recessed surface defining a reservoir for containing a compliant heat transfer material. The assembly may further include a volume of the heat transfer material, such as a liquid metal or thermally conductive gel, in the reservoir of the heat sink. In one embodiment, the optic is a slab amplifier with a reflective coating or layer that directly contacts the heat transfer material in the heat sink reservoir or a foil or membrane is provided between the heat transfer material and the slab.

1 . A method of mounting an optic to a heat sink, comprising:
 providing a metallic heat sink assembly comprising a surface with a recessed portion having a predefined volume;   mounting an optic onto the heat sink assembly such that at least one surface of the optic is positioned proximate to the recessed portion of the surface of the heat sink assembly; and   filling the recessed portion of the heat sink assembly with liquid metal or thermally conductive gel, wherein the liquid metal or thermally conductive gel contacts the at least one surface of the optic.   
   
   
       2 . The method of  claim 1 , further comprising prior to the mounting of the optic, attaching a metallic foil to the surface of the heat sink assembly, the attaching being performed to create a liquid-resistant seal about the periphery of the recessed portion, whereby the liquid metal or thermally conductive gel contacts the metallic foil which in turn contacts the at least one surface of the optic. 
   
   
       3 . The method of  claim 1 , wherein the metallic heat sink assembly further comprises an expansion reservoir of variable volume that is fluidically linked to the recessed portion and wherein the filling of the recessed portion of the heat sink assembly comprises filling the expansion reservoir with a volume of the liquid metal or thermally conductive gel. 
   
   
       4 . The method of  claim 1 , wherein the heat sink assembly comprises a frame holding the optic and wherein the method further comprises after the filling of the recessed portion, detaching a portion of the heat sink from the frame. 
   
   
       5 . The method of  claim 1 , further comprising attaching onto the heat sink assembly means for controlling movement of the mounted optic relative to the heat sink assembly.