A 256/spl times/256 CMOS imaging array with wide dynamic range pixels and column-parallel digital output

A 256x256 CMOS active pixel sensor (APS) is described for an automotive stereo-vision system. Illumination may vary over several orders of magnitude, requiring a high dynamic range imager. Dynamic range is increased 20/spl times/ using a special clocking scheme for the lateral overflow gate. This dynamic range enhancement offers improvements over previously-described techniques. It simultaneously provides flexibility, user-adjustability, and digital control, with no reduction of fill factor. On-chip column-parallel cyclic analog-to-digital converters (ADCs) produce digital output at frame rates from 30 to 390 frames/s.