High-sensitive torsion sensing based on chiral long-period gratings

High-reproducible chiral long-period gratings (CLPGs) are achieved, which are fabricated from normal single mode fibers. To explore torsion sensing application, we investigate the response trend of transmission spectrum versus mechanical twist rate in CLPGs. High torsion sensitivity is achieved, a perfect linear relationship between the resonance wavelength shift and the mechanical twist rate is displayed.