Wide dynamic range CMOS image sensor with in-pixel double-exposure and synthesis

A wide-dynamic-range CMOS image sensor (CIS) based on synthesis of a long-time and a short-time exposure signal in the floating diffusion (FD) of a five-transistor active pixel is proposed. With optimized pixel operation, the response curve is compressed and a wide dynamic range image is obtained. A prototype wide-dynamic-range CMOS image sensor was developed with a 0.18 μm CIS process. With the double exposure time 2.4 ms and 70 ns, the dynamic range of the proposed sensor is 80 dB with 30 frames per second (fps). The proposed CMOS image sensor meets the demands of applications in security surveillance systems.