A fast CMOS optical position sensor with high subpixel resolution

This paper describes a novel architecture for an optical position sensor which has been implemented on a single chip using standard digital CMOS technology. The prototype device consists of 20*20 active pixels and two row and column parallel processing units with corresponding digital decoding logic. The image contour is extracted by means of distributed peakdetection, implemented at pixel level, followed by a digital extraction of the beam centroid position executed at row and column level. The sensor chip achieves up to 3000 frames/s with a position accuracy of 0.013 pixel and a total power consumption of 15 mW at 5 V.