Optical sensing: A new approach to measurements with fiber Bragg grating

Optical sensors have emerged during the telecom boom in the late 1900´s, due to the availability of low-cost telecom-grade optical components. It´s only after the telecom bubble in early 2000 that optical sensors became sufficiently developed to become a viable technology for real-world applications. Optical sensing systems are nonconductive and use light to perform measurements of various phenomena. There several optical sensing technologies available, each with different strengths and weaknesses. FBG-based optical sensing provides distinct advantages for civil measurements because of their multiplexing capability and wavelength-encoded measurement information. In other words, with their ability to serve both as sensing element and signal transmission medium, FBG technology can have a significant impact on structural and physical measurement systems. This paper will present a holistic view of stress/strain measurements, including conventional strain gages and vibrating wires. It will then introduce optical sensing, presenting the different optical sensor technologies. Finally, more details on FBG optical sensing will be provided, including the benefits that make FBG a compelling technology for structural and physical measurement applications.