Novel CMOS image sensor with a 132-dB dynamic range

Abstract

A CMOS image sensor providing an ultrawide dynamic range with a piecewise linear response is presented. The active pixel is based on a novel architecture which implements a voltage comparator and an analog memory to detect and store the information on the integration time needed to reach saturation, while also maintaining the standard integrated photo-current signal. A 128/spl times/64 pixel array has been designed and fabricated in 0.35-/spl mu/m, 3.3-V CMOS technology. The chip measures 2.67/spl times/4.90 mm/sup 2/ with a pixel size of 24.65/spl times/24.65 /spl mu/m/sup 2/ and a fill factor of about 11%. The sensor has been fully characterized and the measured dynamic range turned out to be 132 dB with a power consumption of 14 mW at video frame rate. The sensor features also good noise performance with a temporal noise of 0.2% (1.7%) and a fixed pattern noise of 0.4% (1.5%) at low (high) irradiance.