An analog VLSI implementation of a smart microsensor that mimics the early visual processing stage in insects is described with an emphasis on the overall concept and the front-end detection. The system employs the 'smart sensor' paradigm in that the detectors and processing circuitry are integrated on the one chip. The integrated circuit is composed of sixty channels of photodetectors and parallel processing elements. The photodetection circuitry includes p-well junction diodes on a 2μm CMOS process and a logarithmic compression to increase the dynamic range of the system. The future possibility of gallium arsenide implementation is discussed. The processing elements behind each photodetector contain a' low frequency differentiator where s...