A CMOS optical sensor with on focal plane programmable spatio-temporal filters

A prototype of 34×34 pixels vision sensor with on focal plane image processing is presented. The sensor performs a wide range of image filtering over a 3×3 pixel kernel, based on two operations: absolute value of the difference (AVD) between two signals and signal accumulation (SA). These two functions are implemented at pixel-level thanks to a high pixel connectivity, allowing both pixel parallel computation with large flexibility in coefficients assignment. The pixel occupies 35×35 μm² of chip area with a fill factor of 20%. The total dynamic range of the sensor is 98 dB. The array was fabricated in 0.35 μm CMOS technology and consumes 6 mW @ 3.3 V.