Set of three integrated circuits for digital video signal processing in color-television receivers
US4523222A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 10, 1983 |
| Grant date | Jun 11, 1985 |
| Priority date | — |
| Expiry date | Feb 10, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/64
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In this IC set, the dark currents and the white levels of the three electron guns, the leakage currents of the cathodes, and a light-detector current are measured during four successive vertical blanking intervals. The cathode leakage currents and the dark currents are measured in the first half of the vertical blanking interval, and the light-detector current and the white level currents are measured at the end of this interval. From these measured data and alignment data stored in a reprogrammable memory (ps), a microprocessor (mp) contained together with the memory (ps) in an integrated circuit (ic2) derives operating data for the picture tube (b) as well as further data. These operating data are transferred over a wire of a chroma bus (cb), over which chroma signals are transferred during the vertical sweep, into a shift register (sr) of a further integrated circuit (ic3) at the beginning of each vertical blanking interval, from where they are passed on to the picture tube (b) in groups via digital-to-analog converters and analog amplifiers. By the use of the chroma bus for a dual purpose, and the successive measurements of the above-mentioned picture-tube data, a saving of ext…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.