Color CRT with cross-misconvergence correction device
US6326742A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 1999 |
| Grant date | Dec 4, 2001 |
| Priority date | — |
| Expiry date | Oct 20, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J29/705
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A color cathode ray tube is composed of a glass bulb which has a front panel and a fluorescent screen set on an inner surface of the front panel, an in-line electron gun which is provided in the glass bulb and projects electron beams onto the fluorescent screen, a deflection means including horizontal and vertical deflection coils arranged outside the glass bulb, and a correction device for correcting cross-misconvergence. The correction device is provided with four correction coils that are respectively set for the four quadrants of a rectangular deflection region of the electron beams. The strength of the corrective magnetic fields generated by the correction coils becomes largest when the electron beams are deflected to a horizontal strip in the central part of both the upper and lower halves of the deflection region, and becomes nearly 0 when the electron beams are deflected to areas around the horizontal axis and top and bottom edges of the deflection region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.