Periodically Tapered LPFG for Ethanol Concentration Detection in Ethanol-Gasoline Blend

Abstract

In this paper we report the fabrication of periodically tapered Long Period Fiber Grating (LPFG) in standard single-mode telecommunication fiber using electric arc from a fusion splicer. The ability of the fusion splicer to precisely taper the fiber is effectively utilized for producing periodic tapers in the fiber. The antisymmetric resonant mode of the fabricated LPFG is utilized as a refractive index transducer to measure the ethanol concentration in ethanol-gasoline blends. The work carried out shows that compared with the normal arc induced LPFG, the periodically tapered one shows better refractive index sensitivity.

Keywords

• Fiber optic sensor
• Long period fiber gratings
• Fiber tapering
• Fuel adulteration