摘要 |
<p>A dispenser cathode which comprises an emission surface (4), a reservoir for material releasing (2), when heated, work-function-lowering particles, and at least one passage (7) for allowing diffusion of work-function-lowering particles from said reservoir to said emission surface, said emission surface comprising at least one emission area (9) and at least one non-emission area (8) covered with emission-suppressing material and surrounding each emission area, said non-emission area comprising at least one passage connecting said reservoir with said non-emission area and debouching within a diffusion length distance from an emission area for allowing diffusion of work-function-lowering particles from said reservoir to said emission area.
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