Thermionic emitter designed to provide uniform loading and thermal compensation
US7903788B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 25, 2008 |
| Grant date | Mar 8, 2011 |
| Priority date | — |
| Expiry date | Sep 2, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2235/06
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electron emitter assembly for use in an x-ray emitting device or other electron emitter-containing device is disclosed. In one embodiment, an x-ray tube is disclosed, including a vacuum enclosure that houses both an anode having a target surface, and a cathode positioned with respect to the anode. The cathode includes an electron emitter having a plurality of substantially parallel emission surfaces that collectively emit a beam of electrons for impingement on the target anode. In one aspect, the plurality of substantially parallel emission surfaces are angled relative focusing region so as to provide a substantially uniform thermal load on the target anode. In another aspect, the electron emitter includes a plurality of cut-outs that accommodate thermal expansion in the plane of the emitter. Accommodating thermal expansion in the plane of the emitter prevents distortions to the emitter that would tend to alter the focusing of the electrons on the target anode. Providing a substantially uniform thermal load on the target anode and preventing thermal distortion of the emitter lead to higher x-ray flux and better focusing for higher quality x-ray images.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.