Fiber optic reflector is an optical passive device that allows only certain bands to pass through, using FBG fiber gratings or filters to reflect specific reflection wavelengths back, while normally passing through other communication bands that are not within the specific reflection wavelength range.

The fiber optic reflector has low insertion loss in the transmission wavelength range and high reflectivity in the reflection wavelength range. It is an ideal optical terminal for FTTx network link monitoring and is suitable for point-to-point (PTP) and point-to-multipoint (PTMP) networks. Typically installed in the user's home to highlight these locations in the OTDR trace by the reflection of the test signal.