Electron gun having a cathode with limited electron discharge region
US5990608A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 21, 1997 |
| Grant date | Nov 23, 1999 |
| Priority date | — |
| Expiry date | Nov 21, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J29/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electron gun provides an improved focusing characteristic of electron beams surely and effectively, and permits position alignment to be relatively easy in assembling thereof. In an electron gun which includes a cathode for discharging electrons and a plurality of grids each having electron passing-through holes for guiding the electrons discharged from the cathode unidirectionally, an electron dischargeable region is formed in an electron discharging plane of the cathode, which is band-shaped. In addition, the length of the band-shaped area constituting the electron dischargeable region on its shorter side is less than 80% of the diameter of the area from where electrons are discharged when a practical maximum current is taken out without limiting the electron dischargeable region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.