Method of driving image display device
US5061880A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 16, 1990 |
| Grant date | Oct 29, 1991 |
| Priority date | — |
| Expiry date | Mar 16, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/12
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of driving an image display device is disclosed in which electron beams from line cathodes are impinged upon a display screen through beam modulating and deflecting electrodes to display an image. Each beam roughly lands onto a predetermined position on the screen by a stepped deflection voltage waveform to form a spot on the screen while the beam is deflected around the predetermined position by an unstepped deflection voltage waveform. The timing of application or the pulse width of a driving pulse signal for the beam modulating electrode is controlled in a form temporally related to the driving of the beam deflecting electrode to control the landing position or diameter of the spot on the screen. In the case where the driving pulse signal is a signal the pulse width of which is modulated by a video signal, the pulse width is changed in accordance with the level of the video signal and equally in positive and negative directions around the instant of time when a signal pulse having the minimum width necessary for representation as an image is to be generated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.