Color cathode ray tube with mask frame having beads for rigidity

A color cathode ray tube comprising:

• a vacuum envelope including a panel having a major axis and a minor axis perpendicular to each other;
• a phosphor screen located on the inner surface of the panel;
• an electron gun assembly for emitting electron beams toward the phosphor screen;
• and
• a color sorting mechanism opposed to the phosphor screen,
• the color sorting mechanism including a mask body, having a rectangular effective portion with a large number of electron beam holes, and a mask frame fixedly fitted with the mask body,
• the mask frame including a sidewall portion, composed of a pair of long sidewalls extending parallel to the major axis and opposed to each other, a pair of short sidewalls extending parallel to the minor axis and opposed to each other, and corner sidewalls between the long and short sidewalls, and a base portion extending from the sidewall portion toward a tube axis,
• the base portion having substantially straight beads located near the corner sidewalls and connecting the long and short sidewalls.