Color picture tube having an inline electron gun with an astigmatic prefocusing lens
US5066887A · kind A · utility
13Cited by
12References
14Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Feb 22, 1990 |
| Grant date | Nov 19, 1991 |
| Priority date | — |
| Expiry date | Feb 22, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2229/4872
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A color picture tube includes an inline electron gun for generating and directing three inline electron beams along coplanar beam paths toward a screen. The gun includes a plurality of electrodes which form a beam-forming region, a prefocusing lens, and a main focusing lens for the electron beams. The prefocusing lens includes four active surfaces. At least one of the active surfaces has asymmetric prefocusing recesses formed therein.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.