A differential active pixel sensor

A differential active pixel sensor suitable for implementation in a CMOS process is described. Aspects of sensor operation arising from the differential nature of the pixel are discussed. Artifacts caused by gain mismatches among pixel elements, kTC noise, fixed-pattern noise due to reset mismatches, and corrupted pixels can be reduced using the differential pixel structure. Since the proposed pixel is fully differential, immunity to noise from digital circuits and clocks is also anticipated. The architecture enables scan-based image processing on the image at high data rates while allowing the use of low speed components. The paper focuses on the topology of the differential pixel and the reset/read sequence required to acquire data from the pixel.