Nowadays, the usage of fiber optics is really common in several daily applications such as the telecommunications and sensoristic field. In the telecommunications field, the usage of fiber permits to have many advantages compared, for example, to the usage of copper cables. In fact, the fiber optics allow to transmit a large amount of data and with a high bit rate for long distance. Therefore, they allow doing this with low losses and there is no need to external power supply. In addition to these advantages, the fiber optics are immune to electromagnetic interference and thanks to high temperature resistance and corrosive environment, it is possible to use fiber optics in harsh environment.