CATHODE-RAY TUBE

PURPOSE:To prevent the deterioration of an electron gun cathode and obtain a cathode-ray tube having a long life by forming a conducting film containing activated carbon having a specified specific surface area on the surface of the inner member of a tube body except a fluorescent screen. CONSTITUTION:A conducting film containing activated carbon having the specific surface area 100-3000m /g is formed on the surface of the inner member of a tube body except a fluorescent screen. An effective adsorption capability is exerted, and the activated carbon has a high adsorption capability for the gas apt to poisoning the electron emitting material layer of an electron gun cathode such as CO2 and CO in particular. The high-vacuum state in the tube body is satisfactorily maintained, the deterioration of the electron gun cathode is prevented, and a cathode-ray tube with a long life can be obtained.