Fiber Bragg grating-based temperature-insensitive tilt sensor with optimum response characteristics

We present a simple and novel design strategy, to our knowledge, for the development of an all-optical fiber Bragg grating (FBG) based tilt sensor. The research includes both theoretical analyses and rigorous experimental investigations to establish the response characteristics of the sensor across the dynamic range of ±10^∘. Experimental observation demonstrates a high sensitivity of 0.3198 nm/°, which is capable of being tuned further to any desired value. The sensor is characterized by an excellent accuracy (±0.0031^∘), very low maximum discrepancy (±0.001 nm), and an angular resolution of 0.0016°. The sensor was characterized by insensitivity to temperature variations over the measured approximate temperature range of 25°C to 60°C. Furthermore, the experimental observations establish the sensor response to have a very high degree of reversibility with a maximum forward-to-reverse separation of 0.001 nm over the tested angle range.