通过化学镀的方法，在光纤光栅表面得到了不同厚度的均匀金属镍镀层。由于材料热膨胀系数的差异，金属镍镀层将会在光栅内部形成内应力，这种内应力将随着镀层厚度的改变而改变。理论上分析了金属镀层的厚度对光栅中心波长漂移的影响，获得相关的理论曲线；实验上通过对化学镀镍全过程光纤光栅反射光谱的在线监测，获得了不同镀镍层厚度的光纤光栅中心波长的改变量，实验数据与理论分析结果吻合较好。

By using chemical metallization, nickel layer is coated on the fiber Bragg grating with different thicknesses. The inner stress occurs due to different thermal expanding coefficients between nickel layer and fiber grating layer, which is influenced by metal-film thickness. In this paper, the relationship between the wavelength shift and the thickness of nickel layer is theoretically analyzed. Moreover, the in-situ observation of the fiber grating during electroless plating and the wavelength shift as a function of metal-film thickness are investigated. A good agreement is found between the experimental and calculated results.