Cathode-ray tube apparatus
US6555975B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2001 |
| Grant date | Apr 29, 2003 |
| Priority date | — |
| Expiry date | Jun 29, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J29/503
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A main lens includes a second segment, a sixth grid and an additional electrode disposed between the second segment and the sixth grid. A first-level constant voltage and a second-level constant voltage are applied to the second segment and sixth grid, respectively. A third-level voltage, which is at a level between the first level and the second level, is applied to the additional electrode. In accordance with the increase in a deflection amount of an electric beam, the third-level voltage varies as a value expressed by ((voltage to the additional electrode)−(voltage to the second segment))/((voltage to the sixth grid)−(voltage to the second segment)). An auxiliary lens having lenses including a third grid and a first segment has a focusing power decreasing in accordance with an increase in the deflection amount of the electron beam.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.