Dark current is an intrinsic electronic noise present in all photo-detectors and optical sensors, distinguished by its occurrence in the absence of any incident light. It plays a crucial role in determining the performance and sensitivity of these instruments, especially in low-light conditions. These electrons are indistinguishable from photoelectrons, so they add a false signal that increases with integration time and contributes additional shot noise. It refers to a specific parameter, component, or methodology used in the design, analysis, or measurement of radio frequency systems. Understanding Dark Current is essential for engineers working.