Wavelength demodulated Bragg grating fiber optic sensing systems for addressing smart structure critical issues

Abstract

Smart materials and adaptive structures will require structurally integrated fiber optic sensing systems that can operate in practical situations including harsh environments. The intracore fiber optic Bragg grating has considerable potential to serve as the sensor of choice for this emerging field. However, its role has been impeded by the lack of a simple, passive and fast method of determining the wavelength of its narrow back-reflected optical signal. The authors report on the development of just such a wavelength demodulation system that is inexpensive and easily implemented with a minimum of equipment. Furthermore, they shall show that this approach lends itself to the development of an optoelectronic chip that could process many fiber optic sensors, yet be small enough to be integrated within the structural interface and thereby address the interconnect problem-potentially one of the most critical facing the development of practical smart structures.