Color picture tube with a magnetic focusing device
US4362964A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 29, 1979 |
| Grant date | Dec 7, 1982 |
| Priority date | — |
| Expiry date | Oct 29, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J29/68
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
There is disclosed an in-line type three-gun color picture tube with a couple of magnetic members inside its neck portion and a further magnet outside its neck portion. The respective magnetic members are provided with three through-holes permitting electron beams emitted from the electron guns to pass through and are disposed separately in a beam traveling path, so that the periphery of the through-holes of one of the magnetic members is magnetized in S pole and that of the other magnetic member is magnetized in N pole, and accordingly a focusing magnetic field is formed between the respective pairs of the through-holes which are opposite to each other. The magnetic pieces are disposed between the adjacent through-holes to intensify the magnetic field in the alignment of the through-holes which is weakened due to the presence of the through-holes, so that the focusing magnetic field in the alignment of the through-holes is compensated and accordingly the respective focusing magnetic fields become symmetrical with respect to their axes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.