Apparatus and method for stabilizing image sensor black level
US7760258B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 7, 2007 |
| Grant date | Jul 20, 2010 |
| Priority date | — |
| Expiry date | Jul 23, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/677
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A black clamp stabilization circuit for an image sensor utilizes a mixed-signal SoC block comprising sub-blocks to dynamically and precisely adjust the black level based on comparison to a reference black level. The black level adjustments include a first level regulation using digital control of an analog signal in a feedback loop that includes a programmable gain amplifier and high-resolution A/D converter. By applying the black clamping in the analog domain, dynamic range is extended. Additional black level regulation is subsequently performed in the digital domain to differentially eliminate line noise and column noise generated within the imaging System-on-Chip. By providing information between the sub-blocks, the algorithms can converge more quickly. The technique enables multiple signal paths to separately handle individual colors and to increase imaging data throughput.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.