基于单模微纳光纤基模有效折射率色散方程和光纤布拉格光栅谐振方程，研究单层结构光纤布拉格光栅光谱特性，并用FH酸化学腐蚀法制得单层结构布拉格光栅.理论和实验结果表明：随着光栅半径减小，单层结构光纤布拉格光栅谐振波长蓝移，且谐振波长个数由5个减少到1个，直至最后完全消失；随着光栅外环境折射率的减小，截止半径缩短，当折射率降到1时，截止半径减为0.55 μm.

The spectral characteristics of the single layer optical fiber Bragg grating was analyzed in detail based on single mode effective refractive index of micro-nano optical fiber dispersion equation and the resonance equation of the optical fiber Bragg grating. The single layer optical fiber Bragg grating obtained by FH acid etching.with the decrease of the fiber core radius, the resonance wavelength shift to the lift, and the resonant wavelength numbers are reduced from 5 to 1, until finally disappeared; With the decrease of the refractive index grating external environment at the same time, the cut-off radius reduced, and when the grating external environment refractive index dropped to 1, the cut-off radius reduced to 0.55 μm.