CATHODE-RAY TUBE HAVING INTERNAL MAGNETIC SHIELD WITH STRENGTHENING RIBS

摘要

A color cathode-ray tube (CRT) has a rectangular faceplate panel with a major axis and a minor axis. A viewing screen is disposed on an internal surface of the panel. The panel is sealed to a funnel along an edge of a sidewall of the panel. A color selection electrode assembly is spaced from the screen and attached to the sidewall of the panel. An internal magnetic shield has a substantially rectangular base, with four corners, which is secured to the color selection electrode assembly, and a flange circumscribing an aperture. A substantially continuous shield sidewall extends between the base and the flange. The shield sidewall extends backward along an inner surface of the funnel. The internal magnetic shield is improved by at least two pairs of strengthening ribs which are formed in opposite sides of the shield. The ribs are substantially parallel to the minor axis of the panel and in proximity to the flange of the shield. At least one of each pair of ribs extends around two adjacent corners of the shield sidewall.