Luminance signal processing circuit
US4296435A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 18, 1980 |
| Grant date | Oct 20, 1981 |
| Priority date | — |
| Expiry date | Aug 18, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/208
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A luminance signal processing circuit for a television receiver comprises means for separating a full bandwidth luminance signal into a low pass component and first and second derivative components of the low pass component. A differential amplifier is responsive to the component voltage signals for developing first and second current mode signals representing in phase and 180.degree. out of phase combinations of the low pass and second derivative components. The levels of the second derivative components of the first and second current mode signals are selectively adjusted by a peaking signal processor for developing related third and fourth current mode signals whose amplitudes are also selectively adjusted by a picture signal processor for developing an output luminance voltage having selectively controlled contrast and peaking components. A peak white limiter is responsive to white going portions of the second derivative components of the third and fourth current mode signals for automatically causing a corresponding reduction in the level of the output luminance voltage. Finally, a single supply of DC potential is coupled to the picture signal processor for supplying the bias …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.