In the context of detectors, what is responsivity (R)?

Responsivity (R) in the context of detectors refers to the measure of the output signal generated by a detector in response to a specific level of input radiation. It quantifies the effectiveness of the detector in converting incoming light or radiation into an electrical signal, usually expressed in units such as amperes per watt (A/W) or volts per watt (V/W). High responsivity indicates that a detector can produce a significant output signal with relatively little input power, making it highly sensitive, which is critical in applications requiring precise measurements of low levels of radiation.

This definition aligns closely with the fundamental function of detectors, allowing them to effectively convert various forms of radiation into readable electrical signals for further analysis or interpretation. Understanding responsivity is crucial for selecting the right detector for specific applications, especially in fields like telecommunications, environmental monitoring, and medical imaging, where sensitivity to low levels of radiation is essential.