How can infrared imaging reveal hidden details beneath a painting's surface?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Hear about William Henry Ireland's fake manuscripts of William Shakespeare including a letter written to his wife — Forgery A look at a letter supposedly written by William Shakespeare to his wife, Anne Hathaway; it was, in fact, faked by William-Henry Ireland.

In the context of art forgery, infrared imaging serves as a powerful tool for technical analysis. Because infrared rays possess the ability to penetrate thin layers of paint in an oil painting, they can reveal hidden details beneath the surface that are otherwise invisible to the naked eye.1

This technique is particularly effective for uncovering:

Underpainting: It can expose preliminary sketches or earlier compositions that an artist may have painted over on the same canvas.1
Altered Signatures: It can reveal original signatures that have been painted over and replaced with those of more profitable or famous artists.1

By allowing experts to see through the top layers of pigment, infrared examination helps verify the authenticity of a work by comparing its internal construction to the known habits and techniques of the attributed artist.1