MANUFACTURE OF IMAGE DISPLAYER TUBE

摘要

PURPOSE:To enable a vapordeposition film of an adequate area to be formed through performing flashing only once using a reduced amount of getter material by installing a getter which flashes parallel to the plate-like electrode in the tube before it is sealed and then flashing the getter to form the vapordeposition film. CONSTITUTION:A getter 8 is prepared by placing a getter member 8a in an annular concave 8c on the outer peripheral surface of a ring. For example, the outer diameter of the ring and the amount of Ba per 1cm<2> are adjusted to be about 20mm and 1.3mg respectively. The distance between a vacuum case 1 and an electrode structure 2 is adjusted to 3mm. The ring getter 8 is installed parallel to the plate-like electrode at a level 1.5mm higher than the back surface of the central area of the electrode structure 2. A high-frequency magnetic field is applied to the ring getter 8 to heat it thereby flashing Ba. As the result, Ba scatters parallel to the inner surface of the vacuum case 1 and the back surface of the electrode structure 2 and is then vapordeposited in a circle around the ring getter 8 to form a vapordeposition film 9.