See-through computer display systems

A head-worn computer, comprising:

• a. A computer display positioned to be viewed by a user of the head-worn computer;
• b. Electronics, including a processor, adapted to operate the computer display;
• and
• c. A heat sink arranged to transfer heat generated by the processor to an external surface, wherein the heat sink further includes a plurality of micro-holes of a size to allow a gas to transfer to the external surface while not allowing a liquid to flow through any of the plurality of micro-holes, wherein the micro-holes are positioned to facilitate the transfer of heat from the processor.