Colour CRT with rectangular screen - has greater heat removal from specified regions of shadow mask to reduce beam landing errors

摘要

The colour CRT has a shadow-mask near the screen, which warms up during operation. The shadow-mask has a large number of holes for electron passage, suitably positioned w.r.t. the different phosphors. The shadow-mask and/or the screen are so constructed that higher heat removal is achieved at its horizontal central line, and in regions in the middle between the vertical central line and mask edges. The resulting changes in mask curvature with temp. reduce beam landing errors.