Shadow mask type color cathode ray tube with shadow mask effective to minimize the appearance of Moire patterns
US4983879A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 14, 1988 |
| Grant date | Jan 8, 1991 |
| Priority date | — |
| Expiry date | Dec 14, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J29/076
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A color cathode ray tube which includes an evacuated envelope having a phosphor deposited screen and an electron gun assembly positioned in opposition to the phosphor deposited screen and operable to emit electron beams towards the phosphor deposited screen, and an apertured shadow mask disposed inside the envelope in the vicinity of and generally parallel to the phosphor deposited screen and spaced a predetermined distance from the phosphor deposited screen. The pitch between each of the neighboring apertures in the shadow mask as measured in a vertical direction perpendicular to a horizontal scanning line is chosen to be a value variable as a function of the distance away from the center of the phosphor deposited screen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.