CMOS Cameras: Passive Pixel Sensor Technology

This lecture discusses the evolution and market dominance of CMOS sensors over CCD sensors in camera technology. It highlights the advantages of CMOS technology, which is widely used in electronics, including cameras. The instructor explains the structure and function of photodetectors using CMOS technology, particularly focusing on the photodiode and its integration in image sensors. The lecture details the process of charge collection in a passive pixel sensor, emphasizing the role of the p-n junction and the impact of illumination on voltage reduction. The instructor also addresses the configuration of passive pixel sensors, noting the absence of amplification within each pixel and the implications of this design on signal quality. The challenges associated with large capacitance in passive pixel sensors, such as low conversion factors and increased noise, are discussed, underscoring the trade-offs in sensitivity and noise levels. Overall, the lecture provides a comprehensive overview of the principles and challenges of CMOS camera technology.