A dual pixel-type array for imaging and motion centroid localization

An imager chip has been designed, fabricated, and tested having two unique pixel types interleaved on the same array. The dual-pixel design enables optimization for two separate tasks. One type of pixel is an active pixel sensor (APS), which is used to produce a low-noise image. The other type is a custom-designed pixel optimized for computing the centroid of a moving object in the scene. The APS array is 120 columns ×36 rows, with a pixel size of 14.7×14.7 μm. The centroid array has 60 columns and 36 rows, with a larger pixel size of 29.4×29.4 μm. The chip was fabricated using standard scalable rules on a 0.5 μm 1P3M CMOS process. APS images were taken at a frame rate of 30 fps-8300 fps and centroid data was taken at a rate of 180-3580 (x,y) coordinates per second. The chip consumed 2.6 mW.