Arrangement for generating a beam current indicative signal
US5177413A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 25, 1992 |
| Grant date | Jan 5, 1993 |
| Priority date | — |
| Expiry date | Feb 25, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N3/185
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a vertical deflection circuit, a vertical deflection current is controlled by a vertical sawtooth signal. A transistor generates a first control signal that is derived by sensing the beam current. The control signal is used for modulating the vertical sawtooth signal to compensate for a tendency of the raster height on a screen of a cathode ray tube to increase when the ultor voltage decreases. The transistor also clamps a second control signal that is indicative of the beam current to a predetermined level when the beam current is smaller than a predetermined value. The second control signal is coupled to an automatic beam current limiter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.