Optical power meter (optical power meter) refers to an instrument used to measure absolute optical power or the relative loss of optical power through a length of optical fiber. In optical fiber systems, measuring optical power is the most basic, much like a multimeter in electronics; in optical fiber measurement, optical power meters are commonly used meters for heavy loads. By measuring the absolute power of the transmitting terminal or optical network, an optical power meter can evaluate the performance of the optical terminal equipment. Using an optical power meter in combination with a stable light source can measure connection loss, verify continuity, and help evaluate fiber link transmission quality.