A novel dynamic axial strain sensor based on the bend characteristics of novel long-period fiber gratings（LPFG） written by high frequency CO

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laser pulses is proposed.According to the bend characteristics of the novel LPFG that its resonant wavelength and amplitude are sensitive to the bend curvature

the dynamic strain measurement is accomplished by measuring the change of the bend curvature of LPFG.The theory and experimental results show that the AC voltage measured by the detector increasing with the dynamic axial strain

strain sensitivity is 57.56 mV/10

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.Resolution is 1.6×10

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/Hz and a SNR is 61 dB under a dynamic axial strain of 0.69×10

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at 300 Hz.A simple and low cost dynamic axial strain sensor can be presented by this method.