Fiber optic sensing is not constrained by line of sight or remote power access and, depending on system configuration, can be deployed in continuous lengths exceeding 45 km (30 miles) with detection at every point along its path. A fiber-optic sensor is a sensor that uses optical fiber either as the sensing element ("intrinsic sensors"), or as a means of relaying signals from a remote sensor to the electronics that process the signals ("extrinsic sensors"). Fibers have many uses in remote sensing. Depending on the. A fiber optic sensor measures a physical quantity by modulating the intensity, spectrum, phase, or polarization of light traveling through the optical fiber system. Think of it like a photoresistor, which changes its resistance based. Radiation absorption excites an orbital electron to a higher energy level. Heating the material enables the trapped states to interact with phonons and decay into lower-energy. The fiber optic sensor has an optical fiber connected to a light source to allow for detection in tight spaces or where a small profile is beneficial.
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