A flexible scheme for adaptive integration time control [CMOS image sensor]

A scheme to regulate the integration time in an array of charge integrators, independent of the individual discharging rate, is presented. The regulation scheme can be used for the design of high dynamic range imagers. It has been implemented in a prototype imager realized in a standard 0.25 /spl mu/m CMOS technology, offering a resolution of 170/spl times/170 pixels with a pitch of 75 /spl mu/m. A movable window allows the selection of the region of interest where high dynamic range capability is desired. Experimental results show a dynamic range of 135 dB.