BI-POTENTIAL MASK TYPE CATHODE RAY TUBE

摘要

PURPOSE: A bi-potential mask type cathode ray tube is provided to prevent a getter film from being deposited inside of the skirt part in face panel by controlling a path of getter material discharged in getter flashing process. CONSTITUTION: A face panel(4) includes a skirt part extended vertically from the screen edge. A phosphor film screen(2) forms a plurality of R, G, B phosphor films inside of the face panel screen and is supplied with a predetermined high voltage. A shadow mask(12) keeps in insulation with the phosphor screen and forms an acceleration electric field between the phosphor and the shadow mask by being supplied a bi-potential. A mask frame(18) fixes the shadow mask to the skirt part in face panel. An inner shield(24) is fixed to the rear side of the mask frame and shields a path of the electron beams from the geomagnetic field. A getter(26) makes an inside of bulb high vacuum state by discharging of getter material when the getter filler is heated. A prevent unit prevents the getter film from being deposited inside of the skirt part by blocking a path of the getter material that goes from the getter to the skirt part in face panel.