Color cathode-ray tube having electrostatic quadrupole lens exhibiting different intensities for electron beams
US6400105B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 27, 1998 |
| Grant date | Jun 4, 2002 |
| Priority date | — |
| Expiry date | Apr 27, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2229/4879
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A focus electrode is constituted by a first type of focus electrode group to which a first focus voltage is applied, and a second type of focus electrode group to which a second focus voltage is applied. Between the first type of focus electrode group and the second type of focus electrode group are formed a lens at least having a lens action for correcting the field curvature and an electrostatic quadrupole lens. The center axes of the outer electron beam passage holes in the first type of focus electrode forming the lens at least having a lens action for correcting the field curvature are deviated on a horizontal plane from the center axes of the outer electron beam passage holes in the second type of focus electrode. The electrostatic quadrupole lens produces dissimilar intensities for the outer electron beams and for the center electron beam. Therefore, the outer electron beam passage holes work to deflect the outer electron beams toward the center electron beam with an increase in the deflecting amount of the electron beams, and a favorable resolution is obtained on the whole screen of the cathode-ray tube.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.