Resolving cross sensitivity of fiber Bragg gratings with different polymeric coatings

Abstract

An approach to resolve the cross sensitivity of fiber Bragg gratings (FBGs) is proposed by the adoption of different polymers as the coating materials for gratings. From the different optical responses resulted from the gratings of different polymeric coatings, sensitivity to individual parameter can be exactly revealed. As an application of this approach, simultaneous discrimination of axial strain and temperature with two FBGs of different polymeric coatings is demonstrated with the axial strain and temperature sensitivities of 1.228pm∕με and 11.433pm∕°C for the acrylate-coated FBG, and 1.170pm∕με and 11.333pm∕°C for the polyimide-coated FBG, respectively.