Color picture tube including an electron gun in a coated tube neck
US6559586B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Jul 21, 2000 |
| Grant date | May 6, 2003 |
| Priority date | — |
| Expiry date | Mar 12, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2229/4834
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A cathode ray tube and a plural beam electron gun therefor include a main lens that comprises a tubular focus grid G5 and a conductive coating on the inner surface of the tube neck. The neck coating extends from the region of focus grid G5 towards the faceplate of the cathode ray tube. Preferably, the exit of the focus grid G5 is non-planar and is curved or undulated and focus grid G5 includes an aperture plate intermediate its entrance and exit. The aperture plate preferably has an elliptical center beam opening and connected-semi-elliptical outer-beam openings, to better converge and focus the outer and center electron beams. Also preferably, the focus grid G5 is centrally located in the tube neck and at least partly surrounded by the conductive neck coating.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.