Method and apparatus for deflecting and focusing a charged particle stream
US6614151B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Mar 15, 2001 |
| Grant date | Sep 2, 2003 |
| Priority date | — |
| Expiry date | Mar 15, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J49/28
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method and apparatus is disclosed for electrostatic deflection and focusing of a charged particle stream. The apparatus can include plural vertical and horizontal deflection plates, although a single vertical and a single horizontal deflection plate each with a reference potential plane are preferred. Both orthogonal and preferably tilted display screens are employed to receive the deflected beam. The particle stream is injected offset from a centered position and the stream is deflected asymmetrically relative to the attracting deflection plate. Two alternately preferred computer programs are employable to calculate an offset position. A preferred external quadrupole is employed to correct any residual astigmatism in the particle stream. In one embodiment, the apparatus is disposed in a cathode ray tube. A reduced footprint CRT is also disclosed. Methods and apparatuses for an energy filtered electron beam, a mass spectrometer and a mass separator are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.