光纤光栅反射谱对非均匀应变的展宽响应

光纤布拉格光栅在非均匀应力场作用下，其纤芯折射率及光栅栅距都将产生非均匀变化，本文给出了光纤光栅与非均匀应变场的相互作用模型，建立了反射谱对非均匀应变的响应关系。并给出了线性应力场的实验结果。

Response of Fiber Bragg Grating Reflective Spectrum Expanding to Uneven Distribution Strain

When a fiber Bragg grating is subject to an uneven strain, both of the fiber core index and the grating pitch will experience an uneven variation and therefore the resonant wavelength will vary along the grating. The interaction model between fiber Bragg grating and uneven strain field is established, and the relationship of the fiber Bragg grating reflective spectrum response to the uneven strain is deduced. The results of interaction experiments between linear distribution strain field and fiber Bragg grating are given.