Shadow mask, cathode ray tube, method and apparatus for manufacturing shadow mask

摘要

A shadow mask for use in a cathode ray tube comprises a mask body having a mask effective section where a number of electron beam passage apertures are formed and a skirt portion provided at a peripheral edge of the mask effective section, and a mask frame arranged to be layered outside the skirt portion. The mask frame and the skirt portion are resistance-welded to each other at a plurality of portions. At each welding portion, a plurality of concave and/or convex portions each having a smaller area than an area of a contact surface of an electrode for resistance-welding are formed at an inner surface portion of the skirt portion which the electrode contacts.