Programmable multi-task on-chip processing for CMOS imagers

Programmable multi-task on-chip processing is proposed for improving the performance of CMOS imagers in terms of sensitivity adaptation and image processing capabilities. The current-mode fully analog on-chip processing only performs computations during the readout and analog-to-digital conversion phases, removing the need for any in-pixel or focal-plane processing circuitry. A VLSI implementation, in AMI 0.5 /spl mu/m CMOS process, results in significant silicon area savings as processing circuitry accounts for less than 20% of the imager prototype core area. Only three externally tunable parameters are required to fully define the processing task to be carried out by the 32/spl times/32 CMOS imager prototype, which performs sensitivity adaptation, edge detection or image enhancement on read-out.