| 摘要 |
PURPOSE:To invisualize seam of deflection electrode after exposure by cutting both ends of transparent photomask like a saw tooth in accordance with the specification of deflection electrode pattern and the forming the cylindrical photomask through heat treatment after the saw tooth areas of both ends are alternately engaged. CONSTITUTION:After a vacuum-deposited metal film 2 and a photoresist 3 are formed at the internal wall of tube 1, a cylindrical photomask 4 forming the deflection electrode pattern is inserted, a fluorescent lamp 5 and a air bag 7 are provided at the inside, the air is supplied to the air bag 7 and thereby the bag expands and is closely in contact with the internal wall of photomask 4, and the deflection electrode is formed by exposure. In this case, both ends of photomask 4 are cut like a saw tooth in accordance with the deflection electrode pattern, the cylindrical photomask is formed by combining the saw tooth edges 8 alternately along the shape of cylindrical jig 17 and by heating such photomask with a jig 18. Such cylindrical photomask is molded and hardened. Thereby, the seam of deflection electrode can be invisualized after the exposure. |
