SHADOW-MASK FOR COLOR CATHODE-RAY TUBE

摘要

PURPOSE: A shadow-mask for a color cathode-ray tube is provided to improve impact and vibration characteristic of the color cathode-ray tube by providing a reinforcement structure shapes of beads are reformed to increase the number of the cut end of the shadow-mask. CONSTITUTION: A shadow-mask for a color cathode-ray tube comprises an effective surface(16) on which a number of holes an electronic beam is passed is formed, a non- effective surface formed around the edge of the effective surface(16) and a number of beads(25) each formed on the noneffective surface for intensity reinforcement. The beads (25) are elongated from the noneffective surface to a skirt part of the shadow-mask with maintaining a predeterminded width(W) respectively. Each cut end of the beads(25) has a staircase shape with over two steps. When setting a length of the noneffective surface to L1 and a length of a bead(25) to L2, the ratio of L2 to L1 satisfies an equation 0.3<L2/L1<0.8. When setting a height of the skirt part to h1 and a height of a bead to h2, the ratio of h2 to h1 satisfies an equation 0.3<h2/h1.