Electron beam deflection device for cathode ray tubes which is self convergent and geometry corrected
US5847503A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 1997 |
| Grant date | Dec 8, 1998 |
| Priority date | — |
| Expiry date | Oct 2, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2229/7033
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A deflection device for a cathode-ray tube with three coplanar guns, comprising a pair of horizontal deflection coils and a pair of vertical deflection coils, each horizontal deflection coil having a main deflection winding extending over the length of the deflection device, and an auxiliary deflection winding. Each main deflection winding has a front portion and a rear portion. The auxiliary deflection winding is disposed in the front portion of the main deflection winding and is arranged to generate a magnetic field opposed to a field of the main deflection winding. Each of the auxiliary windings has conductors arranged laterally about a mean angle from a horizontal deflection axis, the mean angle varying as a function of the position of the conductors along a longitudinal axis of the deflection device such that, in the front portion of each of the main deflection windings of the pair of horizontal deflection coils, an amplitude of the third-order harmonic of the Fourier series decomposition of the angular distribution of the ampere-turn density is substantially equal to or greater than that of the fundamental.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.