摘要:
A color picture tube includes a panel of which substantially rectangular effective area has a flat external surface and a curved internal surface, and on the internal surface of the effective area thereof a phosphor screen is formed. The internal surface of the effective area of the panel, when an average radius of curvature in major axis direction is RH, an average radius of curvature in minor axis direction is RV, an average radius of curvature in long side direction is RL and an average radius of curvature in short side direction is RS, is formed in a curved face satisfying RH>RV and RS≧RV, or RH>RV and RS≧RV and RL≧RH. In this color picture tube, flatness of the effective area of the panel and visibility are improved.
摘要:
Provided is a color cathode ray tube, which comprises a panel including a substantially rectangular effective portion, of which the outer surface is a flat surface or a slightly curved surface, and a shadow mask having an effective surface opposite the inner surface of the effective portion of the panel. In this color cathode ray tube, the inner surface of the effective portion of the panel is a curved surface having a substantially infinite curvature radius RXp1 in the major-axis direction on the major axis thereof near the center, a predetermined curvature radius RXp2 in the major-axis direction near peripheral portions on the major axis, and another predetermined curvature radius in the minor-axis direction on the minor axis thereof. This color cathode ray tube, with its panel having the substantially flat outer surface, enjoys improved visibility and higher strength for the maintenance of the curved surface of the shadow mask.
摘要:
In a color cathode ray tube in which the external surface of an effective portion of a panel has a flat surface or a slight curvature, the shadow mask is set such that the layout distance between electron beam through hole array near the long side of an effective surface of the shadow mask is larger in the vicinity of the short axis than the layout distance at the center of the effective surface. Further, the layout distance becomes gradually smaller in direction away from the short axis, and thereafter, the layout distance changes to an increase. In the vicinity of the short side of the effective surface, the layout distance becomes equal to or larger than the layout distance near the short axis. Therefore, the curvature of the shadow mask and the electron beam through hole array are set in proper condition, and mislanding of beam landing due to deformation or oscillation of the shadow mask can be reduced. At the same time, howling of the phosphor screen can be minimized.
摘要:
A color cathode ray tube having a reinforcing band, which constricts the outer periphery of a skirt portion of a vacuum envelope, arranged so as to fulfill a relation, b≧2.0a, where a is the distance between first and second planes along a tube axis, the first plane intersecting an end edge of the skirt portion and extending perpendicular to the tube axis, the second plane containing the central axis of stud pins supporting a shadow mask and extending perpendicular to the tube axis, and b is the distance between the first plane and a third plane along the tube axis, the third plane intersecting a side edge of the reinforcing band facing a vacuum envelope funnel.
摘要:
A color cathode ray tube is provided with a shadow mask having a mask body including a substantially rectangular effective surface in which a large number of electron beam passage apertures are formed. A plurality of reinforcing beads are formed on the effective surface, and project therefrom to have heights which varies in accordance with positions such that in at least a part of an area for provision of the reinforcing beads, the heights of the reinforcing beads satisfy the following relationship: dx1>dx2, dy1>dy2 where dx1 is the height measured at a first position which is apart from a longer axis of the effective surface and a distance x1 apart from a shorter axis thereof, dx2 is the height measured at a second position which is further apart from the longer axis than the first position and a distance x2 apart from the shorter axis, dy1 is the height measured at a third position which is located on the shorter axis and a distance y1 apart from the longer axis, dy2 is the height measured at a fourth position which is a distance apart from the shorter axis and a distance y2 apart from the longer axis, and the distances x1, x2, y1 and y2 satisfy the following relationship: x1=x2=y1=y2.
摘要:
A shadow mask of a color cathode-ray tube includes a substantially rectangular mask main body and a rectangular mask frame attached an outer periphery of the mask main body. The mask main body has a substantially rectangular main surface portion formed of a curved face having a large number of electron beam passage apertures, the main surface portion having a longer axis and a shorter axis perpendicular to the longer axis, and a skirt portion raised in peripheral edges of the main surface portion. The skirt portion has a pair of longer side walls extending substantially in parallel to the longer axis, and a pair of shorter side walls extending substantially in parallel to the shorter axis. Each of the longer side walls includes a pressing portion located near the shorter axis so as to protrude toward the mask frame and pressing the mask frame.
摘要:
In a color cathode ray tube comprising a panel with a substantially rectangular effective portion whose outside face is almost flat or slightly curved and whose inside face has a curvature in the direction of minor axis near the short sides of the portion, and a fluorescent substance screen having a substantially rectangular effective region formed on the inside face of the effective portion of the panel, the short sides in the outer circumference of the effective region of the fluorescent substance screen are projected toward the center of the effective region. This improves the flatness of images appearing on the fluorescent substance screen provided on the inside face of the effective portion in the color cathode ray tube with the outside face of the effective portion of the substantially rectangular panel being almost flat and the inside face having a curvature in the direction of minor axis at least near the short sides.
摘要:
A face panel (12) constituting a part of a vacuum envelope (20) has a substantially rectangular effective area (10), the inner surface of which is formed with a phosphor screen (14). The effective area has a long axis (X) extending in the horizontal direction and a short axis (Y) extending in the vertical direction. The outer surface of the effective area is cylindrically curved with an infinitely large radius of curvature along the long axis and a predetermined radius of curvature along the short axis. The vacuum envelope has arranged therein a shadow mask (15) in opposed relation to the phosphor screen. A mask body of the shadow mask has a substantially rectangular effective surface cylindrically curved with an infinitely large radius of curvature along the long axis and a predetermined radius of curvature along the short axis thereof. In manufacturing the shadow mask, a flat mask is subjected to a plastic deformation into a cylindrical shape curved along the short axis and then subjected to an elastic deformation in such a manner that the radius of curvature thereof is larger than at the time of plastic deformation. The mask body thus formed by elastic deformation is fixed to a rectangular frame.
摘要:
A shadow mask opposing a phosphor screen includes a substantially rectangular mask body having a number of electron beam passage apertures, and a substantially rectangular mask frame having four side walls supporting a periphery of the mask body. Among the side walls, a pair of long side walls each has a central connecting portion which is located at a central portion thereof in lengthwise direction and fixed to the mask body, and a pair of protruding portions which are provided on both sides of the central connecting portion in the lengthwise direction and protrude in a direction apart from the mask body. Each protruding portion defines a gap between the side wall and the mask body, and a width of the gap gradually increases as it goes far from the central connecting portion.
摘要:
A color cathode ray tube comprises a panel having an effective portion. The outer surface in the effective portion of the panel is substantially flat or forms a slightly curved plane with a small curvature. The inner surface of the panel has a substantially infinite curvature radius in a direction of the longer axis in at least a central portion of the panel and is curved in a direction of the shorter axis. A difference in thickness of the effective portion of the panel between the central portion and the edge portions diagonally apart from each other exceeds 8 mm and does not exceed 20 mm, and the transmittance of the glass in the central portion of the effective portion is at least 70%. The particular construction enables the vacuum envelope of the color cathode ray tube to exhibit a mechanical strength high enough to sufficiently withstand the atmospheric pressure, though the effective portion of the panel is flattened. The vacuum envelope also exhibits a mechanical strength high enough to hold the curved surface of the shadow mask. Further, deterioration of brightness can be prevented in the color cathode ray tube of the present invention.