Cathode ray tube display apparatus
US5872432A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 30, 1997 |
| Grant date | Feb 16, 1999 |
| Priority date | — |
| Expiry date | May 30, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2320/08
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Cathode ray tube display apparatus comprises a cathode ray display tube (210) in which an electron beam spot is scanned in a raster pattern to produce an output image. Drive means (200) generates drive voltages on the focus electrode, first and second grid electrodes, and a cathode of the cathode ray tube to generate the electron beam spot in the cathode ray tube. Spot size control means (120) simultaneously varyies, in response to a spot control signal, the voltages generated on the focus electrode, first and second gird electrodes and the cathode by the drive means to vary the size of the electron beam spot in the cathode ray tube.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.