Abstract：A fiber Bragg grating etched by HF solution is applied for refractive index sensing. The dispersion relation equation of fiber is numerically resolved. The reflected spectrum of the fiber grating during etching and sensing is theoretically obtained. The result is applied to design an optimum etching process, and a phase shift fiber Bragg grating is fabricated and applied to measure refractive index of surround solution. The fiber Bragg grating is partial and localized etched to be a phase shift fiber Bragg grating. According to the character of phase shift fiber Bragg grating, a modulation method based on reflected power is developed, the modulation system is convenient and immune to temperature change.
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2011, Vol. 32 
