Fig. 1. Schematic diagram of demodulation based on edge filter

Fig. 2. Fabrication of LPFG

Fig. 3. Influences of different laser output duty cycles and numbers of period on transmission spectrum of LPFG

Fig. 4. Transmission spectrum of LPFG for different numbers of period with weight removed

Fig. 5. Schematic diagram of FBG demodulation device based on LPFG

Fig. 6. Transmission spectrum of ASE broadband light adjusting by LPFG and FBG reflection spectrum

Fig. 7. LPFG-FBG demodulation device diagram

Fig. 8. Temperature characteristic test of LPFG-FBG demodulation method

Fig. 9. Strain characteristic test of LPFG-FBG demodulation method

Fig. 10. Dynamic characteristic test of LPFG-FBG demodulation method