Optical fiber transducer based on LPFG and microbends for multi-parameter sensing

Microbending losses in single-mode fibers have been evaluated by different authors by means of the coupling between the guided mode and a number of discrete cladding modes. Sensors based on microbends have been adapted to many different measurement applications. Long-period fiber gratings are photoinduced fiber devices that have many potential applications as wavelengths dependent filters, for gain flattening of erbium doped fiber amplifier, as strain, temperature, and refractive index sensors. In this work a new optical fiber transducer for the measure of four different parameters such as temperature, strain, external index of refraction and pressure based on long period fiber grating and microbends is proposed and analysed.