Integrating sphere

An integrating sphere, also known as an integrating cavity or a light integrating sphere, is an optical device used to measure and distribute light uniformly across its inner surface. It is typically made of a hollow sphere with a highly reflective interior coating, such as barium sulfate or white paint. The design and structure of an integrating sphere allow it to collect light from various angles and redistribute it uniformly, making it an essential tool in various applications, particularly in photometry and radiometry.