一、引言在彩色显像管方面,近年来国际上倾向于在保证伦琴辐射不超过安全限度的条件下,尽可能使用较高的屏电压,以进一步改善显像管的分辨率和提高亮度。这是因为在忽略空间电荷和电子透镜的像差时,电子束管荧光屏上的光点半径Υ_(?)反比于屏电压V的平方根,即 I. INTRODUCTION In the field of color picture tube, in recent years, the international tendency is to use higher screen voltage as much as possible under the condition of ensuring that the radiation of the roentgen does not exceed the safety limit, so as to further improve the resolution of the picture tube and improve the brightness. This is because, when ignoring the space charge and the aberration of the electron lens, the spot radius Y_ (?) On the electron beam tube phosphor screen is inversely proportional to the square root of the screen voltage V, that is,