A 120x160 pixel CMOS Range Image Sensor based on Current Assisted Photonic Demodulators

In this paper a Time-Of-Flight range camera based on Current Assisted Photonic Demodulators is presented. The sensor, fabricated in a 0.18 mu m CMOS technology, features 120x160 pixel resolution with 10 mu m pixel pitch and 24% fill factor. Pixel, camera and system architectures are described highlighting the most important design issues, and a selection of experimental results is presented. The chip has a power consumption of 200mW, mainly due to the contribution of modulation current. A range camera system was realized using the proposed sensor, a focusing optics providing a 23 degrees x30 degrees field of view, and a 3-LED illumination module delivering 140mW optical power on the target. The system is capable of acquiring a stream of 7 3D frames/s with a maximum non-linearity of 3.3% in the range 1.2m-3.7m and a precision better than 10 cm at 2m and 20 cm at 3m.