The change of both physical length and strain-dependent refractive index of the fiber, are calculated by altering the bend radius of the sensor. In this example, a bend sensor based on fiber Bragg grating (FBG) is demonstrated. We observed a high resolution of the sensor at a level of 3. Their simplicity of operation coupled with attractive and unique features, such as all-fiber construction. A variation of the period of the grating inscripted in a fiber optic – induced by mechanical or thermal perturbation – causes a shift of the reflected peak wavelength, due to the related optical path length variation.
