Electron beam source assembly
US5418348A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 29, 1992 |
| Grant date | May 23, 1995 |
| Priority date | — |
| Expiry date | Oct 29, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C14/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electron beam source assembly includes a water cooled crucible positioned substantially flush with the top of the block. A magnet is attached to each long sides of the rectangular block to establish parallel opposed pole magnets with the crucible therebetween. A smaller magnet is attached to each end of each longitudinal magnet to form a second and a third parallel magnet pair. The six magnets produce plano-convex magnetic field lines above the crucible, and additional plano-convex field lines of increased field strength extending outwardly from the end of the block having the four magnets. A magnetic base plate provides a low reluctance path to decrease magnetic flux at the crucible. An electron gun emitter mechanism is sheltered from vapors formed at the crucible and includes architecture to enable electrons to be freely emitted from the filament, without being subjected to the magnetic field lines from the magnet pairs, in a direct path outwardly through an open cavity and through a window formed in the end of the electron source assembly. The freely emitted electron beam assumes a trajectory passing solely through plano-convex magnetic field lines to produce an inverted imag…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.