Color picture tube having an improved expanded focus lens type inline electron gun
US4590402A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 31, 1984 |
| Grant date | May 20, 1986 |
| Priority date | — |
| Expiry date | Aug 31, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2229/4896
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An improved color picture tube has an inline electron gun for generating and directing three electron beams, a center beam and two side beams, along coplanar paths toward a screen of the tube. The gun includes a main focusing lens for focusing the electron beams. The main focusing lens is formed by two spaced electrodes, each having three separate inline apertures therein. Each electrode also includes a peripheral rim. The peripheral rims of the two electrodes face each other. The apertured portion of each electrode is within a recess set back from the rim. The recesses of the electrodes have substantially the same dimension perpendicular to the inline directions of the inline apertures as the dimension parallel to the inline direction of the inline apertures. However, the recesses have lesser dimensions along diagonals angled at approximately 45 degrees with respect to the inline direction of the inline apertures. The electrodes are connected by four support rods that are peripherally attached to the electrodes along the diagonals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.