Wide-angle deflection color cathode ray tube with a reduced dynamic focus voltage
US6304026A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1999 |
| Grant date | Oct 16, 2001 |
| Priority date | — |
| Expiry date | Mar 2, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2229/4841
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A color cathode ray tube includes a phosphor screen, an in-line type electron gun having an electron beam generating section for projecting three electron beams arranged in parallel with each other in a horizontal plane toward the phosphor screen, a focus electrode, and an anode adjacent to the focus electrode and forming a main lens in cooperation with the focus electrode for focusing the electron beams on the phosphor screen. The focus electrode includes at least a first focus sub-electrode and a second focus sub-electrode on the order named from the cathode, the first focus sub-electrode and the second focus sub-electrode forming an electrostatic quadrupole lens therebetween. An axial distance Lgf (mm) from an end of the first focus sub-electrode on a cathode side thereof to an end of the second focus sub-electrode on an anode side thereof, an axial distance Ls (mm) from the end of the second focus sub-electrode to the phosphor screen, and a useful diagonal dimension D (mm) of the phosphor screen satisfies a following relationship: 0.06.times.Ls (mm).ltoreq.Lgf.ltoreq.26 (mm), and 1.50.ltoreq.D/Ls.ltoreq.1.70.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.