Patent ID: 6812627
Filing Date: 2004-11-02
Classification: H01J

Abstract:
An apparatus, comprising:a tension mask having a screen part for transmitting electron beams, the screen part having a first area including a center region of the screen part, and having a second area distinguishable from the first area and not including the center region of the screen part; and a mask frame coupled to said tension mask for reinforcing structural strength of said tension mask while applying tension to said tension mask; the screen part including a plurality of real slots, dummy slots and strip parts, the real slots being located in the first area, the dummy slots being located in the second area; the screen part having a first edge region substantially parallel to an X axis, the first area being symmetrically formed around a first imaginary line parallel to the X axis, the first area being symmetrically formed around a second imaginary line perpendicular to the X axis; the first area being concavely shaped in a middle region of the second imaginary line.