Mask frame assembly and color CRT using the same

A tension mask frame assembly comprising:

• a tension mask having a plurality of slots formed in a Y direction and having long side edges along an X direction, where tension is applied to said tension mask along the Y direction;
• and
• a frame having support members to support said tension mask at the long side edges in the X direction and to apply the tension to said tension mask,
• wherein:
• a mis-landing of an electron beam due to thermal expansion of the tension mask frame assembly is corrected by a change in a radius of curvature that is expressed in an equation as ΔRz=C×Rz2, in which
• C is a thermal drift correction coefficient for the tension mask frame assembly to correct the thermal expansion due to heat generated by a mis-landing of electron beams on said tension mask,
• Rz is a radius of curvature before the thermal expansion of the long side edges of said tension mask along a Z axis, which is a direction perpendicular to both the X and Y directions, and
• ΔRz is an amount of change of the radius of curvature in the Z axis direction when said tension mask and said frame thermally expand.

A tension mask frame assembly comprising:

• a frame including:
• first and second support members separated a predetermined distance from each other, and
• first and second elastic members installed between the first and second support members to support the first and second support members, each of the first and second elastic members having support portions connected by a connection member, each of the support portions being fixed to a corresponding one of the first and second support members;
• a mask having a plurality of electron beam passing holes and installed such that tension is applied by the first and second support members;
• and
• a correction unit installed at the first and second support members or at the support portions between the connection portion and said mask, said correction unit to correct a thermal expansion of said mask and said frame caused by a mis-landing of an electron beam on said mask,
• wherein the thermal expansion due to the mis-landing of the electron beam is corrected by a change in a radius of curvature that is expressed in an equation as ΔRz=C×Rz2,
• C is a thermal drift correction coefficient of the tension mask frame assembly,
• Rz is a radius of curvature before the thermal expansion along a Z axis, which is parallel with an axial direction of the support portions, and
• ΔRz is an amount of change of the radius of curvature in the Z axis direction of said mask while being supported at the first and second support members when said frame, said mask, and said correction unit thermally expand.

A color CRT comprising:

• a panel having a fluorescent film formed on an inner surface;
• a tension mask frame assembly installed in said panel and including
• a frame, the frame including
• first and second support members separated a predetermined distance from each other,
• first and second elastic members installed between the first and second support members to support the first and second support members, each of the first and second elastic members having support portions connected by a connection portion, each of the support portions being fixed at a corresponding one the first and second support members,
• a mask having a plurality of electron beam passing holes and installed such that tension is applied by the first and second support members, and
• a correction unit installed at the first and second support members or at the support portions between the connection portion and the mask, the correction unit to correct a thermal expansion of said tension mask frame assembly caused by a mis-landing of an electron beam on the mask,
• wherein
• the thermal expansion of said tension mask frame assembly is corrected by a change in a radius of curvature that is expressed in an equation as ΔRz=C×Rz2,
• C is a thermal drift correction coefficient of said tension mask frame assembly,
• Rz is a radius of curvature before the thermal expansion along a Z axis, which is parallel to an axial direction of the support portion, and
• ΔRz is an the amount of change of the radius of curvature in the Z axis direction of the mask supported at the first and second support members when the frame, the mask, and the correction unit thermally expand;
• a funnel sealed to said panel, said funnel having a neck portion and a cone portion;
• an electron gun installed in the neck portion of said funnel;
• and
• a deflection yoke installed at the cone portion of said funnel.

A tension mask frame assembly comprising:

• a tension mask having slots formed in a first direction and which is supported along edges in a second direction, where tension is applied to said tension mask along the first direction;
• a frame which supports said tension mask along the edges in the second direction, said frame comprising an elastic member which applies the tension to said tension mask in the first direction;
• and
• a correction unit connected to said frame and which restricts a thermal expansion of said frame in the first direction,
• wherein said correction unit has a thermal expansion coefficient which is less than a thermal expansion coefficient of the elastic member.

The tension mask frame assembly of 28, wherein:

• the angle cross section has a bottom side roughly parallel with said tension mask and another side extending in the third direction from the bottom side,
• the bottom side extends from the another side by a distance W,
• the another side extends from the bottom side by a distance H, and
• a ratio of H to W is at or between 20% and 100%.