Pascal Cotte, a French scientist, claims to have found another portrait beneath that of the world-famous Mona Lisa. Using reflective light technology, Cotte has spent more than 10 years analysing Leonardo Da Vinci’s masterpiece. He claims to have found an underlying image of a model looking off to the side. The Louvre Museum in Paris, which houses the work, has not commented on Cotte’s alleged discovery.

The scientist is the co-founder of the Paris-based company Lumiere Technology, which works closely with galleries and museums to digitize their fine-art pieces. Its website claims to have digitized works by Marc Chagall, Claude Renoir, Pablo Picasso and Vincent Van Gogh. The Louvre granted Cotte access to the Mona Lisa in 2004, the BBC , which is airing a documentary about the discovery, reports.

The hidden image lacks both the Mona Lisa’s famed direct gaze and her smile. Cotte claims he found it by projecting intense light onto the portrait. A camera then measured the lights’ reflections, which allowed Cotte to reconstruct what was created with each layer of paint. This technique is known as Layer Amplification Method.