GETTER DEVICE FOR LARGE-SIZED ELECTRON TUBE

PURPOSE:To provide a getter device capable of giving a certain amount of barium splash which permits satisfactory responding to a super-large electron tube. CONSTITUTION:A ring-shaped vessel 1 of metal with the over-part left open is filled with mixture powder 2 chiefly containing barium-aluminum alloy powder and Ni powder, followed by compression and molding processes. In this getter device, the over-surface of the mixture powder 2 is molded in taper form 4 heightening from the peripheries toward the center, and a plurality of heat emitting members 6 are fixed to the peripheral side-faces of vessel. As a result, temp. rise of the ring-shaped vessel and getter material is made uniformly, and a buoyant phenomenon of the getter material is suppressed, and a sufficient amount of barium splash is obtained.