Production method of cathode ray tube

A welding route of welding a color selecting electrode to a frame is as follows: first of all, a welding head moves down onto one end portion of a long frame side (Step I), welding is conducted from the end portion toward a center portion of the long frame side (Step II). Then, after moving up once (Step III), the welding head moves horizontally toward the other end portion of the long frame side (Step IV) and moves down onto the long frame side (Step V), and welding is conducted from the other end portion toward a center portion of the long frame side (Step VI). Finally, the welding head retracts (Step VII). With this welding route, the generation of wrinkles in the vicinity of the end portions of the long sides of the color selecting electrode can be suppressed.