摘要 |
A glass bulb for cathode-ray tubes the effective screen size of which along the diagonal direction of a glass panel (10) is 500 mm or more, and the average radius of curvature of the outer face of a face portion is 10,000 mm or more, wherein the ratio of the length h of a skirt portion (13) of the glass panel to the distance H along the tube axis from the edge face of the funnel gas-tightly joined to the glass panel to the reference line is within a predetermined range in connection with the deflection angle theta of the funnel representing the substantial spread angle in the direction of the tube axis of the funnel, and whereby the variation of the full length of the glass bulb due to the reduction of the length of the panel skirt portion is corrected by the expansion of a funnel body portion, the weight of the glass panel is decreased while maintaining the specific mechanical strength, and damage during the frit seal heat treatment is prevented.
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