The birefringence of a π -phase-shifted fiber Bragg grating can be determined with high accuracy by measurement of the polarization-induced spectral splitting of its narrow central transmission window. The use of this feature for sensing of a load applied in the direction transverse to the optical fiber is demonstrated. A distributed force resolution of 1.4×10<sup>-3</sup> N/mm was obtained, which corresponds to a difference in the principal strains of the fiber core of 0.5μ∈ . We also show that the transverse load response of the sensor is insensitive to temperature.
© 1999 Optical Society of America
Michel LeBlanc, Sandeep T. Vohra, Tsung E. Tsai, and E. Joseph Friebele, "Transverse load sensing by use of pi-phase-shifted fiber Bragg gratings," Opt. Lett. 24, 1091-1093 (1999)