Patent ID: 6545401
Filing Date: 2003-04-08
Classification: H01J

Abstract:
A color selection apparatus for a cathode ray tube comprising:an iron mask having a longitudinal axis and a short axis; and a frame coupled with the mask and tensing the mask in one direction of the longitudinal and short axes; the mask comprising a plurality of strips spaced apart from one another at predetermined intervals, and a plurality of electron beam through holes formed by a plurality of real bridges arranged between the respective strips at predetermined pitches; wherein a center point of the mask along the longitudinal axis is A, both end points of the mask along the longitudinal axis are B, a length of a longitudinal side of the mask is 2L, points greater than L/4 from the point A in each direction are C, a tension applied to the strip of the point A is smaller than a tension applied to the strips of the points B, and a distribution curve of a tension applied to the strips of the mask along the longitudinal direction satisfies the following equation; |SA-C|C-B|wherein SA-C represents a slope of a straight line that links the point A to one of the points C on the tension distribution curve and SC-B represents a slope of a straight line that links the one point C to the corresponding point B on the tension distribution curve.