Experimental Characterization of Optical Fiber Long Period Grating with Reduced Temperature Sensitivity

Abstract

Abstract-In this paper we show the experimental characterization of optical fiber long period grating for the reduced temperature sensitivity by optimizing the refractiveindex profile of the host fiber. In Long Period Fiber grating the fundamental guided mode light couple with the into copropagating cladding modes at various wavelengths. The two layer Geometry later on the three layer geometry which is useful for refractive index sensing sensing application. The sensitivity of LPFGs to environmental parameters is influenced by the period of the LPFG by the order of the cladding mode to which coupling takes place and by the composition of the optical fiber. A novel method to compensate the temperature sensitivity using a boron co-doped germanosilicate core fiber is used as a host fiber. The Theoretical Characteristic Results matches with the experimental results which demonstrate that such gratings with reduced temperature coefficient retain their capability to detect strain and ambient index variations.Index Terms-LPFG, FBG, refractive index, temperature sensitivity, cladding Mode, OSA.