| 摘要 |
PURPOSE:To obtain an excellent magnetic-focusing-type cathode-ray tube, which has a high reliability and in which three beams are concentrated with the magnetic-focusing device itself, by providing each of opposed magnetic yorks with at least independent three cylindrical parts, and making the plate thickness of the side cylinders larger than that of the center cylinder. CONSTITUTION:Opposed magnetic yorks 52 and 52' have cylindrical parts 53, 54 and 53', 54', which face to each other, so that each of three beams passes through a different pair of cylindrical parts 53, 53' or 54, 54'. In the magnetic york 52 on the negative electrode side, the plate thickness of the center cylinder 53 is made larger than that of the side cylinders 54. In contrast, in the magnetic york 52' on the screen side, the plate thickness of the center cylinder 53' is made smaller than that of the side cylinders 54'. A magnetic field formed with the magnetic yorks 52 and 52' with such shapes tends to concentrate on the center cylinder 53 with a large thickness in the york 52, and tends to concentrate on the side cylinders 54' with a large thickness in the york 52'. |
