The bridges between apertures located at the edge of the shadow mask of a color display tube are made at least 20% wider than the others. The width of the bridges increases linearly from row to row from the center to the edge of the mask whereby a continuously varying brightness distribution is obtained. The reproduction mask used in the fabrication of such a shadow mask can be made photographically by exposing photosensitive material through a pattern of bridges, rotating the pattern and repeating the exposure.
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