Shadow mask colour CRT with vertical phosphor strips - has shadow mask positioned to permit excitation of three adjacent phosphor elements by passed electron beams

摘要

The vertical phosphor elements on the cathode-ray tube screen are grouped in threes for emission of different colours. The perforated shadow mask is spaced from the screen inner face and has corrugations extending vertically. The mask (42) is mounted in a distance (2-7) extending the first order of the screen (32) spacing. The adjacent phosphor element in each group of three strips are energised by parts of the electron beams (38) which penetrate different aperture in the mask. Pref. the distance between mask and screen meets an equation related to spacing of deflection plane to screen, the spacing between the mask apertures parallel to a line through two beams in the deflection plane, and the spacing between the middle CRT long axis and the centre of an electron beam in the deflection plane outside this axis.