| 摘要 |
PROBLEM TO BE SOLVED: To prevent the beam mis-landing that is caused by the vertical deflection of a horizontal magnetic field at a location near a panel corner by dividing an external magnetism shielder into the right and left sides at the outer circumferences of a panel and a funnel with a prescribed space secured between the shielding bodies to shield the magnetic flux which are applied from outside. SOLUTION: Divided right and left external magnetism shilders(EMS) 21 are placed outside of a panel 2 and a funnel 3 of a CRT 1 with a proper space secured between both EMSs 21. Thus, the EMSs 21 are placed at right and left sides, to cover the panel 2 and the funnel 3 and the gaps 21a are secured at upper and lower parts of both EMSs 21. With such a constitution, each gap 21a functions as a high magnetism resistance means, which increases the resistance to the magnetism that is horizontally permeated in each EMS 21. As a result, a horizontal magnetic field applied to each EMS 21 with not receive deflection which would permeate through the upper and lower sides of the EMS 21. Then since no vertical component is given to the horizontal magnetic field, the beam mis-landing that is caused by a vertical component will not occur.
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