Color cathode ray tube with a reduced dynamic focus voltage for an electrostatic quadrupole lens thereof
US6339300B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 15, 2001 |
| Grant date | Jan 15, 2002 |
| Priority date | — |
| Expiry date | Mar 15, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2229/4841
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A color cathode ray tube has G1-G5 electrodes and an anode. The G5 electrode is divided into sub-electrodes supplied alternately with a first fixed focus voltage and a second focus voltage which is a second fixed voltage superposed with a dynamic voltage, at least one electrostatic quadrupole lens is formed between adjacent ones of the sub-electrodes, and two of the sub-electrodes are supplied with the second focus voltage. The following inequalities are satisfied: 0.0625×L (mm)≦B−20A/(3&phgr;)≦22.0 mm, L (mm)≦352 mm, where A is an axial length of the G4 electrode, &phgr; (mm) is an average diameter of a center aperture in the G4 electrode, B (mm) is a length from a cathode side end to a phosphor screen side end of said G5 electrode to the phosphor screen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.