Noise Sources in Optical Detectors: Analysis and Implications

This lecture covers the various noise sources affecting optical detectors, focusing on shot noise, thermal noise, gain noise, and 1/f noise. The instructor begins by introducing the concept of shot noise, which arises from the discretization of physical phenomena, emphasizing its calculation in terms of the number of events. The discussion then shifts to thermal noise, also known as Johnson noise, highlighting its relation to thermal energy and measurement uncertainty. The lecture further explores gain noise, which amplifies both the signal and the associated noise, and the implications of this amplification on signal-to-noise ratios. Additionally, the instructor addresses 1/f noise, often referred to as flicker noise, and its occurrence in various detectors. The impact of background radiation on detector performance is also examined, noting how it contributes to offset noise and fundamental detection limits. Throughout the lecture, the instructor provides mathematical formulations to quantify these noise sources, offering a comprehensive understanding of their significance in optical detection systems.