Color cathode ray tube apparatus

Abstract

In a color cathode ray tube apparatus including an electron gun assembly having a main electron lens section for focusing and converging three electron beams arranged in a line on a phosphor screen, three electron beam through holes arranged in a line in the arrangement direction of the three electron beams are formed in each of the opposing surfaces of the first electrode having a relatively low potential and a second electrode having a relatively high potential, which electrodes constitute the main electron lens and substantially oppose, the pair of side beam through holes of the second electrode are decentered outward in the arrangement direction of the three electron beams with respect to the pair of side beam through holes of the first electrode, and each of the pair of side beam through holes of any one of the first and second electrodes is formed to have a substantially horizontally elongated shape in which both sides in the arrangement direction of the three electron beams are constituted by arcs and the length of, in the case of the first electrode, the length of the inner arc is larger than the length of the outer arc while, in the case of the second electrode, the length of the inner arc is smaller than the length of the outer arc. The three electron beams can be properly focused to obtain good image characteristics on an entire screen.