Image sensor with double integration time and conditional selection
US8686341B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 22, 2012 |
| Grant date | Apr 1, 2014 |
| Priority date | — |
| Expiry date | Sep 12, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/589
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image sensor for gathering images at one and the same time at low illumination level and at high illumination level is described. The sensor operates with a double integration time at each frame. Two successive charge transfers from a photodiode to a storage node are performed, the first after a first duration, the second after a second duration different from the first. The potential of the storage node after the first transfer of charge is sampled in a first capacitor of the reading circuit. The potential after a reinitialization of the storage node is sampled in a second capacitor. A level of potential taken after the second transfer is conditionally resampled in the first capacitor. The condition of the resampling is a condition of signal level after the first transfer. This level is applied to the differential amplifier of a ramp-type converter for a short duration of ramp.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.