Definition & Meaning of "claude glass"

What is a "Claude glass"?

A Claude glass is a small, portable mirror with a dark, tinted surface used by artists and travelers in the 18th and 19th centuries. It was named after the French landscape painter Claude Lorrain, known for his idealized scenes of nature. The tinted mirror reduces colors and details, creating a framed view of the landscape that looks like a classic painting. Artists would use it to plan their drawings or paintings, capturing a more balanced and pleasing artwork.