The rapid development of photonics and photonic devices has brought about a revolution in many areas of basic and applied science.Optical sensors extend the endurance and the response in time and wavelength of the human eye.In order to access the biomedical and environmental spheres with their numerous processes,and for controlling industrial and technological procedures,sensors based on optical spectroscopy offer many attractive features,including high sensitivity and selectivity,non-intrusiveness and data availability in quasi real time.