HDTV colour cathode ray tube shadow mask - has length of openings in mask equal to multiple of distance between adjacent scanning lines

摘要

The cathode ray tube includes a rectangular shadow mask (74) with two long sides and two narrow sides. A main axis (X) runs through the middle of the mask, parallel to the long sides, a near axis (Y) runs through the middle of the mask parallel to the narrow sides. The mask contains slit-shaped openings (36) in columns parallel to the near axis. Neighbouring openings in each column are separated by small tie-bar bridges (38) in the mask. Electron beams are scanned over the whole screen in scanning lines, which run parallel to the main axis. The length (h) of the openings is equal to a multiple of the middle to middle distance between neighbouring scanning lines, measured in the direction of the near axis. ADVANTAGE - Reduces moire patterns to minimum especially.