Lasers and Art

Interesting story about using lasers to clean artwork from the BBC this weekend.

This application (and its cousin, removing tattoos) didn't make it into Chad's laser smackdown, but it is an interesting combination of applied physics and chemistry.

What was interesting to me was that they have had to design lasers with the specific frequency needed so the energy gets deposited in the grime rather than the paint of the frescoes they are using it on, and also research the duration of the pulse so the damage is limited to the undesirable material and not the pigments or surface coating on the wall.

What struck me as really clever was using a laser underwater to do in situ cleaning of a coin in a shipwreck. It must be really useful to identify the value of an archaeological site without having to excavate a found object and bring it back to the lab.