the energy that it takes for the expanding metal to push the gas is more than the heat energy that is transferred to it from the gas

i would think that the force of the gas stops the metal from expanding. When the metal and gas are at the same temperature, they would both be under the...

Or this: #-Link-Snipped-#

Possibly you could set up a forward facing camera to detect glare, and an eye tracking camera, and then triangulate the point of the display where the glare is, and...