So that’s how laser cleaning works

In his July 10, 2014 New York Times article,“Nearly 3,500 Years Old, an Egyptian Monument Gets a Laser Cleaning”, about the cleaning of “Cleopatra’s Needle” (the Egyptian obelisk that stands in Central Park behind the Metropolitan Museum of Art), David W. Dunlap provides a very clear, concise explanation of how laser cleaning works. Anyone needing to explain laser cleaning to a lay person might well appropriate this –with credit to Dunlap, of course.