Capillary-Based Structural Long-Period Gratings for High-Sensitivity Curvature and Strain Measurement

A structural long-period gratings built with cascaded-sections of capillaries for high-sensitive curvature and strain measurement is proposed and experimentally demonstrated, and the correspondent sensitivities of 29.58 dB/m
^-1
and -18.9 pm/$\mu \varepsilon$ could be achieved, respectively.