What is the detector of an optical power meter called

The detector of an optical power meter is called a photodiode or photodetector.

In an optical power meter, the photodiode (or photodetector) is the key component that converts incident light into an electrical signal proportional to the optical power being measured . These detectors are typically made from semiconductor materials such as silicon for short-wavelength light, or germanium and InGaAs for longer wavelengths, depending on the fiber optic system . The photodiode generates a photocurrent when illuminated, which is then amplified using a transimpedance amplifier and converted to a digital signal via an analog-to-digital converter for display and analysis . The choice of detector material and type is crucial for accurate measurements, as the responsivity varies with wavelength, and calibration ensures the meter provides precise readings across the intended spectral range . Some optical power meters also use sensor heads that may include additional optics or attenuators to extend the measurement range or accommodate different beam sizes . Overall, the photodiode serves as the heart of the optical power meter, enabling reliable and precise measurement of optical signals in fiber optic systems.