Using Lasers To Save Earth's Cultural Monuments
History is unwritten by the destruction of great artifacts. Six of the seven wonders of the ancient world are gone, fallen into ruin and sold for scrap, and it is only through historical memory that we know of them. Preserving modern wonders for posterity is the main inititiative of CyArk, a nonprofit that uses 3-D laser scanning to create a digital archive of the world’s cultural heritage sites.
Key to CyArk is a portable, eye-safe laser scanner, made by CyArk founder Ben Kacyra. The scanner is a LIDAR system, which is like radar except instead of bouncing back radio waves it uses lasers. LIDAR systems existed before CyArk, but they were mainly used in labs, where someone would bring an object and get it scanned. (Parts of the music video for Radiohead’s “House of Cards" were recorded this way).
Kacyra's company built a scanner that could work outside, off battery power, and didn’t require special protective shielding for eyes. The scanner is also equipped with a picosecond timing mechanism adapted from one used by Los Alamos Labs to measure underground nuclear tests. This picosecond timer gives the laser scans accuracy down to a millimeter.