Post-deflection acceleration CRT system
US4160187A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 1976 |
| Grant date | Jul 3, 1979 |
| Priority date | — |
| Expiry date | Sep 23, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J29/81
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Improvement is provided in a color cathode ray tube of the post-deflection acceleration type, in the form of an operational system including related tube geometry. An electron barrier, consisting of a metallic film having a defined voltage penetration threshold, is adheringly disposed on the surface of the screen. The potential on the screen is in the order of substantially 20 to 40 kilovolts while the potential of the related color-selection electrode is more than substantially 72 percent and less than 85 percent of the screen potential thereby effecting a definitive voltage differential (.DELTA.V) therebetween that is substantially equal to or less than the voltage penetration threshold of the metallic film. The improvement in the system provides enhanced contrast and color purity in the screen display and minimizes background luminescence of the screen resultant from spurious impingement of secondary electrons generated in the tube.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.