In-line electron gun

An in-line electron gun comprising:

• a plurality of cathodes disposed parallel to each other, adjacent electron guns having beam axes separated by a first distance S.sub.1 ;
• a control grid electrode having a plurality of through-holes, the centers of which are separated by said first distance S.sub.1 ;
• an accelerating electrode having a plurality of through-holes, the centers of which are separated by said first distance S.sub.1, each respective electron gun beam axis being concentric with corresponding respective through-holes of the control grid electrode and the accelerating electrode;
• a first focusing electrode having a surface facing the accelerating electrode containing a plurality of through-holes, the centers of which are separated by a second distance S.sub.2 greater than said distance S.sub.1, another surface of said first focusing electrode, opposite the surface facing the accelerating electrode, having a plurality of vertically oblong through-holes, the centers of which are separated by a third distance S.sub.3, which is less than said distance S.sub.1 ;
• a second focusing electrode having a surface facing the first focusing electrode with one or more horizontally oblong through-holes, respective centers of which are coincident with respective centers of the vertically oblong through-holes of said first focusing electrode, another surface of said second focusing electrode, opposite the surface facing the first focusing electrode, having a plurality of through-holes, the centers of which are separated by a fourth distance S.sub.4, which is less than said third distance S.sub.3 ;
• and
• an anode having a surface facing the second focusing electrode with a plurality of through-holes, the centers of which are separated by said fourth distance S.sub.4 and concentric with the corresponding respective through-holes of said second focusing electrode separated by the distance S.sub.4, wherein:
• said first focusing electrode receives a fixed focusing potential and said second focusing electrode receives a dynamic potential which changes to a potential higher or lower than the fixed focusing potential in response to an increase of the electron beam deflection angle.