Thank you. I was wondering where they got the extra energy from, as IR is less energetic than visible. Did they use two photons to get one (ie, reduce the int

Thank you. I was wondering where they got the extra energy from, as IR is less energetic than visible. Did they use two photons to get one (ie, reduce the intensity)? No. They use a separate light source. So the advantage here over current tech is that you are able to see the visible also, it seems. That is, you're looking through glass and getting all of the visible plus enhanced IR.