X-ray tube electron sources
US7512215B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 23, 2004 |
| Grant date | Mar 31, 2009 |
| Priority date | — |
| Expiry date | May 9, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2235/068
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An X-ray tube includes an emitter wire (18) enclosed in a suppressor(14, 16). An extraction grid comprises a number of parallel wires (20) extending perpendicular to the emitter wire, and a focusing grid comprises a number of wires (22) parallel to the grid wires (20) and spaced apart at equal spacing to the grid wires (20). The grid wire are connected by means of switches to a positive extracting potential or a negative inhibiting potential, and the switches are controlled so that at any one time a pair of adjacent grid wires (22) are connected together to form an extracting pair, which produce an electron beam. The position of the beam is moved by switching different pairs of grid wires to the extracting potential.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.