Optical Fiber Sensing Applications: Detection and Identification of Gases and Volatile Organic Compounds

Optical fiber has produced an authentic revolution in the field of communications. Nowadays, the principal guided data networks of the world use this media. The great success in optical communications raises the question of whether this technology could be also used in other fields, for instance, in the development of sensors. Optical fiber exhibits small dimensions, it is light weight and it is made of an inert and abundant dielectric material, vitreous silica. Even so, regarding to the sensors domain, electronic technology is much more advanced and mature: miniaturization allows mass production and hence, electronic sensors have affordable prices. Photonic devices currently have a justifiable cost in main infrastructures and networks, but they are still less competitive than electronic sensors in applications where there is a wide-spread deployment. Even though the increasing demand for optical devices is reducing its price, some researchers believe that, to be realistic, the success in the communication field does not have to be applicable in sensor technology (Leung, 2001). This idea is far from being pessimistic: applications whose requirements could be satisfied better by the intrinsic features of optical fiber than the ones of electronic devices, have to be identified: for instance, gyroscopes are Optical Fibre Sensors (OFSs) that have been successfully used to measure rotations (Lee, 2003).