Charged particle beam scanning device
US3979636A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 21, 1974 |
| Grant date | Sep 7, 1976 |
| Priority date | — |
| Expiry date | Nov 21, 1994 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2893/0031
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A plurality of control plates is sandwiched between a cathode and a target to control the flow of charged particles such as electrons and ions between the cathode and the target. The cathode includes an elongated filament for generating charged particles such as electrons. A first electrode is positioned behind the filament with a second electrode having a positive potential interdigitated with the first electrode. The first electrode is divided into segments with a negative potential applied to those segments of first electrode where emission is desired from the elongated filament, and in those areas were emission is not desired those segments of the first electrode are switched sufficiently negative to cut off emission from the elongated filament. Each control plate has a plurality of apertures formed therein which are effectively aligned with corresponding apertures on the other control plates. The aligned apertures form beam channels. The control plates have paired conductive electrodes thereon arranged at predetermined coded finger patterns. Voltages are selectively applied to the control plate electrodes by switching circuitry to focus the charged particles through the apertu…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.