Display device and cathode ray tube

A display device having a cathode ray tube with an in-line electron gun, wherein the electron gun comprises:

• a plurality of cathodes;
• a first common electrode having a plurality of first openings adjacent said plurality of cathodes;
• a second common electrode having a plurality of second openings adjacent said first common electrode;
• a third common electrode having a plurality of substantially circular third openings adjacent said second common electrode;
• a fourth common electrode having a plurality of rectangular fourth openings adjacent said third common electrode;
• a fifth common electrode having a plurality of rectangular fifth openings adjacent said fourth common electrode;
• a sixth common electrode adjacent said fifth common electrode, said sixth common electrode having a first plurality of rectangular sixth openings that are proximate said fifth common electron, and a second plurality of rectangular sixth openings that are disposed away from said fifth common electrode;
• and
• a seventh common electrode having a plurality of rectangular seventh openings adjacent said sixth common electrode,
• wherein grid voltages are applied to said first and second common electrodes, a focus voltage is applied to said fourth and sixth common electrodes, and a variable second focus voltage is applied to said third, fifth, and seventh common electrodes.

A display device having a cathode ray tube with an in-line electron gun, wherein the electron gun comprises:

• a plurality of cathodes;
• a first common electrode having a plurality of first openings adjacent said plurality of cathodes;
• a second common electrode having a plurality of rectangular second openings adjacent said first common electrode;
• a third common electrode having a plurality of rectangular third openings adjacent said second common electrode;
• a fourth common electrode having a plurality of rectangular fourth openings adjacent said third common electrode;
• a fifth common electrode having a plurality of rectangular fifth openings adjacent said fourth common electrode;
• and
• a sixth common electrode having a plurality of sixth openings adjacent said fifth common electrode;
• and
• a grid voltage applied to said second and fourth common electrodes, a focus voltage applied to said third and fifth common electrodes, and a potential applied to said sixth common electrodes, wherein a pre-focusing field is formed between said second and third common electrodes.