Ultra low noise CMOS imager
US7929035B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 8, 2007 |
| Grant date | Apr 19, 2011 |
| Priority date | — |
| Expiry date | Feb 19, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/78
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A column buffer for use with a pixel cell array includes an amplifier coupled to three read-out circuits in parallel providing a signal corresponding to accumulated photon-generated charge in a pixel cell plus noise, a reset level plus noise, and a pedestal level, respectively. These three signals are used to generate an ultra-low noise signal Di=Si−Pi-1−G*(Ri−Ri-1), wherein S is the sampled signal, P is the pedestal level, R is the reset level, and G is a gain associated with a pixel cell, and wherein i is a frame number greater than 0. The three signals can be read-out simultaneously. In another embodiment, the three signals are obtained from a column buffer having only one output. In this case, the signals are read-out sequentially.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.