Gaussian-Strain-Chirped Fiber Bragg Grating Couple for Temperature-Insensitive and Intensity-Referenced Force Measurement

A technique for temperature-insensitive force measurement via strain-induced Gaussian-strain-chirped fiber Bragg grating (FBG) couple and differential optical power detection is proposed and experimentally demonstrated. For a temperature range from -10degC to 80degC , a linear force measurement with thermal fluctuations less than 2.5% full-scale is achieved by simply using cost-effective p-i-n photodiodes without any temperature compensation.