摘要 |
A shadow mask is formed by lapping a main mask and an auxiliary mask on each other. The auxiliary mask includes a porous portion having electron beam passage holes, nonporous portions situated individually at the opposite ends of the porous portion, a pair of skirt portions extending individually from the nonporous portions and lapped on the skirt portion of the main mask, and second beads formed individually on the skirt portions and overlapping first beads of the main mask. The height or width of the first beads and the second beads in a superposed portion in which the main mask and the auxiliary mask are lapped on each other is differentiated from that of the beads in non-superposed portions outside the superposed portion. |