This article explores the different types of Fiber Optic Sensors, their working principles, and various applications. A sensor is a device that measures a physical quantity and converts it into a. 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. As a sensing technology based on the principles of optical fiber, fiber optic sensors have gradually become key equipment in many industries due to their advantages, such as high precision, strong anti-interference, and long transmission distances.