Cathode-ray tube for displaying coloured pictures.

摘要

A cathode ray tube for displaying coloured pictures of the post-focusing type. The colour selection means (7) are formed by a plate (20) which is provided with a large number of apertures (9), which plate (20) is provided on one side with a first grid of parallel strips (21) of hard magnetic material provided between the rows of apertures (9). The colour selection means (7) are magnetized in a direction perpendicular to the plane of the plate (20) so that a magnetic quadrupole is . obtained in each aperture (9).