Color cathode ray tube apparatus
US6479951B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 2001 |
| Grant date | Nov 12, 2002 |
| Priority date | — |
| Expiry date | Dec 21, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J29/488
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A color cathode ray tube apparatus of this invention includes an electron gun. In the electron gun, an intermediate electrode is arranged at the mechanical center between a focus electrode and anode electrode that form a rotationally symmetric bi-potential lens. A disk-like intermediate electrode is arranged at the mechanical center between the focus electrode and intermediate electrode. The disk-like intermediate electrode has an electron beam hole with a diameter larger in the vertical direction than in the horizontal direction. The intermediate electrode has a circular electron beam hole. Voltages are applied to the disk-like intermediate electrode and intermediate electrode such that they form an electron lens similar to that formed when the disk-like intermediate electrode does not exist. Therefore, an electron beam spot is focused in an optimal manner on the entire surface of a phosphor screen, and elliptic distortion is decreased. A good image is displayed on the entire surface of the phosphor screen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.