Image sensors having dark pixels and imaging pixels with different sensitivities

    公开(公告)号:US10785431B2

    公开(公告)日:2020-09-22

    申请号:US16200789

    申请日:2018-11-27

    IPC分类号: H04N5/359 H04N5/355

    摘要: An image sensor may include an array of imaging pixels. Each imaging pixel may include a first sub-pixel that is configured to generate a high light-sensitivity signal and a second sub-pixel that is configured to generate a low light-sensitivity signal. The image sensor may also include a plurality of dark pixels that are shielded from incident light and processing circuitry. The processing circuitry may be configured to, for each imaging pixel, compare a value based on at least one of the high light-sensitivity signal and the low light-sensitivity signal to a threshold, modify the high light-sensitivity signal for the respective imaging pixel based at least on the low light-sensitivity signal for the respective imaging pixel when the value is less than the threshold, and modify the high light-sensitivity signal for the respective imaging pixel based on at least one dark pixel signal when the value is greater than the threshold.

    Low power shared image pixel architecture

    公开(公告)号:US11509843B2

    公开(公告)日:2022-11-22

    申请号:US16948784

    申请日:2020-10-01

    摘要: An image sensor may include a shared pixel circuit having multiple photodiodes coupled to a common floating diffusion node via respective charge transfer gates. First, the pixel circuit may be reset, and a sample-and-hold reset (SHR) value may be read out. Charge from a first of the photodiodes may be transferred to the floating diffusion node, and a first sample-and-hold signal (SHS) value may be read out. A first correlated double sampling (CDS) value is obtained by computing the difference between the SHR value and the first SHS value. Without resetting again, charge from a second of the photodiodes may be transferred to the floating diffusion node, and a second SHS value may be read out. A second CDS value is obtained by computing the difference between the first and second SHS values. Reading out the shared pixel circuit in this way substantially reduces power consumption.