Electron beam source, electron optical apparatus using such beam source and method of operating and electron beam source
US6828565B2 · kind B2 · utility
6Cited by
14References
21Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 26, 2003 |
| Grant date | Dec 7, 2004 |
| Priority date | — |
| Expiry date | Sep 26, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/065
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electron beam source comprises a source surface illuminated with a photon beam of adjustable intensity. The photon beam assists emission of electrons from the source surface due to a photo effect. An electric extraction field further assists in electron emission. Further, a heater is provided for further assisting in electron emission by a thermionic effect. An electron beam current is measured, and the intensity of the photon beam is adjusted based on the measured electron beam current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.