The connection between laser radiation and millennia-old archeological sites is not always that obvious (other than Harrison Ford playing both Han Solo and Indiana Jones of course), but the fight to preserve our cultural heritage requires high-tech solutions, and a new article published in the SpringerOpen journal Heritage Science looks at exactly that.
The article, by Paraskevi Pouli and colleagues from the Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (IESL-FORTH), is the first of a collection of articles entitled “Shedding light on the past: Optical technologies applied to cultural heritage.” The series is being Guest Edited by Professor Demetrios Anglos and is celebrating the work carried out in 2015’s “International Year of Light and Light-based Technologies” by showcasing the use of light in the discovery, analysis and preservation of cultural heritage.
In “The two-wavelength laser cleaning methodology; theoretical background and examples from its application on cultural heritage objects and monuments with emphasis to the Athens Acropolis sculptures,” Pouli et al. focus on a process called ‘two-wavelength laser cleaning.’ As discussed in the paper, one of the drawbacks of laser cleaning is that discoloration can occur on the original historical material. To overcome this, the researchers used two laser beams, overlapping in time and space. By utilizing both infrared and ultraviolet frequencies, the laser cleaning left little discoloration on surface material, while preserving the historical layers.
This laser cleaning technique was then applied to the sculptures and monuments from the Acropolis of Athens, the ancient citadel in Greece. The beautiful architectural elements of this site have been exposed to weathering for over 2,000 years, and in more recent history, industrialization and air pollution have led to a build up of soot and other deposits not easily removed.
As with all Heritage Science articles, the full text is open access and free to read, so please take look. The article collection “Shedding light on the past: Optical technologies applied to cultural heritage” will continue to publish exciting articles in this field over the next few months, so watch this space!