PURPOSE: To prevent a cathode ray tube from being affected by magnetic flux by providing a return piece on a shield main body composed of a soft magnetic substance so as to be separated from the outer peripheral surface and extended for more than a fixed distance backward from the front edge of the shield main body on the front panel side of the cathode ray tube.
CONSTITUTION: A return piece 8 is formed integrally with a main body 7 so as to be raised from the front edge of the shield main body 7 to an outer side direction and to be extended backward, for example. A length A of the return piece 8 is set to 50mm at least so that the concentration of magnetic flux 3 can be positioned backward as much as possible and no influence can be exerted upon the front panel of a cathode ray tube 6. A distance to the base of a return material is set to 5-150mm since the magnetic flux is concentrated to the end part of the shield main body when a dimension B is less than 5mm and there is a problem for outer appearance when the B is more than 150mm. Thus, a shield effect is improved, a magnetic shield member can be arranged in a conventional enclosure and the outer appearance is made satisfactory.
ISHII HIROYOSHI
TODA YUKIO
NISHIMURA KAZUHIRO
