Optical black level control circuit
US7714913B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 21, 2005 |
| Grant date | May 11, 2010 |
| Priority date | — |
| Expiry date | Mar 11, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/68
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical black level control circuit comprises a digital black level adjusting circuit for generating a black level correction signal by digital processing using a given time constant when an output error between an optical black level and a reference optical black level signal is within a predetermined range so that an error becomes less than a predetermined value and an analog black level adjusting circuit for compensating for said error when said error exceeds the predetermined range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.