Automatically collimating electron beam producing arrangement
US5235244A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 8, 1992 |
| Grant date | Aug 10, 1993 |
| Priority date | — |
| Expiry date | Sep 8, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J3/022
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An arrangement for and method of automatically collimating an expanding electron beam emitted from a field emission cathode is disclosed herein. This is accomplished without an externally powered colimating or focusing electrode. Rather, a dielectric member is positioned around the path taken by the beam so that when the beam is initially turned on, it bombards the dielectric member with free electrons and thereby places a negative electrostatic charge, ultimately reaching the potential of the cathode electrode itself, on the dielectric member. This electrostatic charge, in turn, causes the cross-sectional configuration of the beam to contract.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.