An over 200-dB dynamic range CMOS image sensor combining a lateral overflow integration with photo-current readout operation

A wide dynamic range 64×64 CMOS image sensor with 20×20μm² pixel that combines a lateral-overflow integration voltage-readout operation with the current readout operation from the buried photo-diode has been developed. In the voltage readout operation, an over 160-dB dynamic range image with a linear response is obtained from sequential electronic shutter operations from 1/30 s to 1/130 ks with a dynamic range of about 100-dB within a light intensity range from about 10^-2lx to 10⁶lx. In addition, an over 200-dB dynamic range performance of up to 10⁸lx or more with few time exposures in the high illuminance region is made possible by combining it with the current reading operation. More than 40 dB for all noises, including photon shot noise, occurs around all the switching points.