Simple temperature insensitive fiber Bragg grating based tilt sensor with enhanced tunability

A design for an all-optical temperature insensitive fiber Bragg grating (FBG) based tilt sensor is reported. The sensor is capable of measuring the magnitude as well as the direction of inclination from the horizontal with a complete reversible response over the designed dynamic range of ±45°. The most important feature of the reported sensor is its inherent enhanced tuning capability for its sensitivity. An excellent sensitivity of the order of ̃0:0626nm=° that can further be tuned is observed for the sensor. Experimental results show that a tilt angle resolution better than 0:008° with a tilt accuracy of ̃ ± 0:36° was achieved.