Electron gun in CRT

Abstract

Electron gun in a CRT including a main lens electrode having a focus electrode and an anode for focusing electron beams emitted from cathodes onto a screen, an electrostatic field controlling body fitted in each of the focus electrode and the anode each having three electron beam pass through holes, wherein each of outer holes in the electrostatic field controlling body fitted to each of the focus electrode and the anode has a form of a combination of a circle and a rectangle with reference to a vertical axis through a center of the hole in a direction opposite for facing outer holes of the focus electrode and the anode, thereby enlarging a main lens diameter, and providing a spot substantially circular and smaller.

Dependencies are inferred from the claim text.