Color cathode ray tube having a small neck diameter
US6448704B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 11, 2000 |
| Grant date | Sep 10, 2002 |
| Priority date | — |
| Expiry date | May 11, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2229/4841
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A color cathode ray tube includes an evacuated envelope formed of a panel portion having a phosphor screen on an inner surface thereof and housing a shadow mask, a neck portion and a funnel portion connecting the panel portion and the neck portion, and an in-line electron gun housed in the neck portion. The in-line electron gun includes a main lens and an electrostatic quadrupole lens. The focus electrode of the electron gun has a single opening at one end thereof for passing the three electron beams and opposes an anode to form a main lens therebetween. The single opening has a diameter larger in a horizontal direction than a diameter thereof in a vertical direction. A distance from the main lens to the phosphor screen is not larger than 300 mm, a vertical mask aperture pitch on a vertical center line of the shadow mask is not larger than 0.28 mm at a center of the shadow mask, and an outer diameter T of the neck portion housing the in-line electron gun satisfies the following inequality 23.2 mm≦T≦25.9 mm, and a value D of twice a distance from a center of a trajectory of a side electron beam of the three electron beams to a horizontal edge of the single opening satisfies th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.