Front end elements for a color cathode ray tube
AssigneeKabushiki Kaisha Toshiba
InventorsMichihiko Inaba, Masaharu Kanto, Satoshi Shikanai, Yasuhisa Ohtake
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Abstract
A front end element, such as a shadow mask, for a color cathode ray tube is made from an alloy including iron and nickel as its principal components; and a black oxide layer is formed integrally on the alloy base. The black oxide layer consists essentially of a spinel-type oxide with the formula Ni.sub.x Fe.sub.(3-x) O.sub.4, where x is a positive number less than 3. A front end element constructed in this way produces a higher quality picture because of reduced thermal expansion.
Claims18
A front end element for a color cathode ray tube, said front end element being selected from the group consisting of a shadow mask, a mask frame, and an inner shield, said front end element having:
- a based consisting of an alloy having iron and nickel as its principal components;
- and
- a black oxide layer formed integrally on said base, said black oxide layer consisting essentially of complex oxide material including iron and nickel, said complex oxide material having a spinel-type structure.
In a color cathode ray tube comprising an envelope having a neck portion at one end and a panel portion at another end, electron gun means in said neck portion for emitting an electron beam, a phosphor screen on an inner surface of said panel portion to emit light upon bombardment by the electron beam, a shadow mask having a plurality of apertures, a mask frame supporting said shadow mask at a predetermined distance from said phosphor screen, and an inner shield attached to said mask frame to shield the electron beam from magnetic flux, the improvement wherein at least one of said shadow mask, said mask frame, and said inner shield comprises:
- a base consisting of an alloy having iron and nickel as its principal components;
- and
- a black oxide layer formed integrally on said base, said black oxide layer consisting essentially of complex oxide material including iron and nickel, said complex oxide material having a spinel-type structure.
Dependencies are inferred from the claim text.