ART - Discovering hidden art: Detective work using terahertz radiation

Damaging biocides can be detected on old wooden sculptures, hidden wall paintings can be made visible again and the layered structures of pieces of art analyzed. Using terahertz scanners restorers will soon be able to identify quickly, and completely non-destructively, what is happening with an object of art.
http://www.sciencedaily.com/releases/2012/11/121121130707.htm