| 摘要 |
The invention relates to image sensors with active pixels. To obtain a wide dynamic operating range, the pixels are read by performing a double charge integration, during periods of different values (Ti1, Ti2). The result of the first integration (period Ti1) is sampled (command SHS1) in a sampling capacitor, and the result of the second integration (period Ti2) is conditionally sampled (command SHS2) in the same capacitor. This second sampling depends on the observation of the potential of the column conductor after the integration of charges corresponding to the longer period; this potential is compared to a threshold. If the comparison indicates a risk of saturation, the information collected during the shorter period is collected and retained in the sampling capacitor in order for it to be multiplied by a coefficient representing the ratio between the longer period and the shorter period. If the comparison indicates that there is no risk of saturation, the information collected during the longer period is collected and retained in the sampling capacitor. The shorter period is, in principle, the first period. |
