We report on a systematic investigation of the dependence of both temperature and strain sensitivities on the fiber Bragg grating type, including the well-known Type I, Type IIA, and a new type that we have designated Type IA, using both hydrogen-free and hydrogenated B/Ge codoped fibres. We have identified distinct sensitivity characteristics for each grating type, and we have used them to implement a novel dual-grating, dual-parameter sensor device. Three dual-grating sensing schemes with different combinations of grating type have been constructed and compared, and that of a Type IA-Type IIA combination exhibits the best performance, which is also superior to that of previously reported grating-based structures. The characteristics of the measurement errors in such dual-grating sensor systems is also presented in detail.
© 2004 Optical Society of America
Xuewen Shu, Donghui Zhao, Lin Zhang, and Ian Bennion, "Use of Dual-Grating Sensors Formed by Different Types of Fiber Bragg Gratings for Simultaneous Temperature and Strain Measurements," Appl. Opt. 43, 2006-2012 (2004)