| 摘要 |
PURPOSE:To obtain an electrode having the good focusing properties by a method, in which the coining underholes are formed on the spots corresponding to the electron beam pass holes of a thick plate material followed by premolding the concaves and thickening the groove edges and flattening the thickened part while performing a stamping process after forming the concaves. CONSTITUTION:The prescribed coining underholes 11 are formed on the spots corresponding to three electron beam pass-holes on a thick plate material 10. Next, while coining by premolding the concaves 12 of the nearly same shape to the prescribed oval concaves on one base of the material 10, the thickened part 13 is coining-processed around the groove edges of the concaves 12. The thickened part 13 is formed by pressing the continuous V-shaped grooves 14 on the thickened part. While subsequently flatening the thickened part 13, a coining process is performed for forming the prescribed oval concaves 22. next, the external form of the material 10 is processed by stamping to a prescribed size for forming an electrode 15 of the oval thick plate shape in order to manufacture the electrode 17 for the electron gun by continuously processing three electron beam pass-holes 16A-16C by stamping to a prescribed size. In this way, the main lens aperture can be increased thus obtaining the electron gun electrode having the good focusing properties. |
