A: Radiation resistant, radiation tolerant or non-browning lenses are all terms used to refer to a lens designed for use in a radioactive environment such as is encountered in the nuclear industry and spaceborne applications. When exposed to Gamma or X-ray radiation most optical materials will change colour, typically dark brown or grey, resulting in almost total loss of transmission. Resolve Optics is an internationally trusted supplier of radiation resistant fixed focus and zoom lenses based upon Cerium doped glasses. These glasses will initially change colour slightly when exposed to elevated levels of radiation but then they will stabilise and maintain high transmission for an extended period of time.
Learn more: https://www.resolveoptics.com/why-use-cerium-doped-glasses/