• It is a scanning technique that uses extremely high frequency waves to penetrate dense surfaces.
• Originally employed in the search for petroleum reserves, it is now used in art restoration.
• The beams can penetrate layers of paint introduced in varying degrees by artists to create particular effects or it can also plumb, without causing damage, layers of wear-and-tear over the years.
• Without the signal processing, researchers might only be able to identify layers 100 to 150 microns thick.
• But using the advanced processing, they can distinguish layers just 20 microns thick.
• Paintings done before the 18th century have been challenging to study because their paint layers tend to be very thin.
• Beyond old art, the non-destructive technique also has potential applications for detecting skin cancer, ensuring proper adhesion of turbine blade coatings, and measuring the thickness of automotive paints.

Source:TH