| 摘要 |
PURPOSE:To suppress a discharge current by making a distance from the reference surface to the end surface of an inner magnetic shield larger than the distance from the reference surface to the anode button while being smaller than the distance to the funnel reference line. CONSTITUTION:Regarding the plane formed by the pannel funnel welding part as the reference surface, the distance L2 from said surface to the end surface extended to the cone part 2a of an inner magnetic shield 26 is so made that the relation 2L2=L1+L3 may be held when the distance to the anode button 10 measured likewise is made to be L1 and the distance to the bulb reference line 27 is made to be L3. The getter 24 is fixed to the tip of a metal holding piece 23 extended from a frame 5 to the cone part 2a while providing the part, where the inner magnetic shield 26 is opposed to the getter 24, with an opening window 26. Since the getter material is mostly scattered within the cone surface having a vertical angle theta while sticking to the inner magnetic shield 26 on the cone part 2a, the resistance value of a high resistance film 8 does not change so as to have a fully satisfying effect of suppressing a discharge current. |
