PURPOSE: To form index signal generation phosphor narrow stripes and prevent smears and ununiformities from occurring by forming a protective film on the phosphor film and a metallic thin film as a metal back and coating organic solvent and surface activator.

CONSTITUTION: The phosphor narrow stripes 3B inside the face panel 1 is covered by the polyvinyl alcohol thin film 4. The thin film 4 forms a protective film together with organic material 5. The metallic thin film section 9' which is entered through the pinhole 8 of the metallic thin film 9 adheres on the surface of the protective film 5'. When organic solvents are coated in this stage, the protective film 5' fills up the pinhole. Subsequently, after surface activators are coated and index signal generation phosphor narrow stripes are formed, such organic materials as protective films are eliminated by heating.