Patent ID: 6894444

Claim:
A color cathode ray tube comprising: a panel having a phosphor screen on an inner surface thereof; an electron gun which emits electron beams toward the phosphor screen; and a substantially rectangular shadow mask located opposite the phosphor screen inside the panel and having a major axis and a minor axis extending at right angles to each other and to a tube axis, the shadow mask including a main mask opposed substantially to the whole area of the phosphor screen and having a number of electron beam passage apertures, and an auxiliary mask fixedly lapped on the main mask in a region containing the minor axis and having a plurality of electron beam passage apertures corresponding to a part of the phosphor screen, the main mask including an effective portion formed having the electron beam passage apertures, a nonporous portion situated around the effective portion, a skirt portion, and first beads located substantially covering the whole circumference of the skirt portion, the auxiliary mask including a porous portion formed having the electron beam passage apertures, nonporous portions continuous individually with the opposite ends of the porous portion in the direction of the minor axis, a pair of skirt portions extending individually from the nonporous portions and superposed on the skirt portion of the main mask, and second beads formed individually on the skirt portions and situated overlapping the first beads of the main mask, and the height or width of the first and second beads in a superposed portion in which the main mask and the auxiliary mask overlap each other being different from that of the beads in non-superposed portions outside the superposed portion.