Its basic function is to detect nearby objects, such as your ear, and automatically turn off the screen during a call. A fiber optic sensor measures a physical quantity by modulating the intensity, spectrum, phase, or polarization of light traveling through the optical fiber system. It's a device that converts light rays into electronic signals. Think of it like a photoresistor, which changes its resistance based. Fiber optic sensor is a new branch in fiber optics in competition with the existing communication system. Fiber optic sensors play a key role in developing the communication system to sense & measure the change within. 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").
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