Reflection spectrum characteristics of FBG based on interference principle

Bragg condition equation is one of the most important fundamental theories for FBG sensor, and has important value for the study of the mechanism of FBG sensors. The reflection spectrum characteristics of FBG were studied and the Bragg condition equation was obtained by the aid of the light interference principle. The analysis shows that the result derived by the light interference principle is consistent with the one deduced by the coupled-mode theory.