Patent ID: 6885140
Filing Date: 2005-04-26
Classification: H01J

Abstract:
1. A color picture tube, comprising: a glass panel that has a skirt part being in a substantially rectangular frame-shape; a frame that holds a shadow mask at an inside thereof, the frame being in a substantially rectangular shape; and a support spring that elastically supports the frame at an inside of the skirt part, the support spring being fixed to (a) a first position that is at an inside surface of a long side of the skirt part, and to (b) a second position that is at an outside surface of a side of the frame facing the long side of the skirt part, the first position and the second position being away from each other in a direction of a horizontal axis, the second position being more away from a vertical axis than the first position, the horizontal axis being perpendicular to a tube axis of the color picture tube and being substantially parallel to the long side, the vertical axis being perpendicular to both the tube axis and the horizontal axis, wherein materials for the support spring and the frame are selected so that, in the direction of the horizontal axis, a thermal expansion amount of the support spring between the first position and the second position is substantially same as a thermal expansion amount of the frame between the second position and the vertical axis when the color picture tube is operated, wherein the first position is on the vertical axis, and the materials for the support spring and the frame are selected so that a difference between a thermal expansion coefficient of the support spring and a thermal expansion coefficient of the frame is in such a range that causes both end parts of the frame in the direction of the horizontal axis to be moved outward with respect to the vertical axis, in the direction of the horizontal axis, when the color picture tube is operated, each of the end parts being moved by substantially a same distance.