提出了一种基于Er-Yb掺杂磷酸盐玻璃的长周期波导光栅,利用耦合模理论研究了长周期波导光栅的传输特性,分析了长周期光栅的相位匹配特性,讨论了光栅常数和光栅长度对长周期波导光栅传输特性的影响。研究结果表明,2个谐振波长对应于相同的辐射模,当光栅长度一定时,长周期波导光栅的带宽随光栅常数的增加而增大;而当光栅常数一定时,长周期波导光栅的带宽随光栅长度的减小而增加,滤波深度随光栅长度的减小而减小。 A long-period waveguide grating based on Er-Yb doped phosphate glass was proposed. The transmission characteristics of the long-period waveguide grating was studied by using the coupled-mode theory. The phase matching characteristics of the long-period grating were analyzed. The grating constant and grating length Effect on long-period waveguide grating transmission characteristics. The results show that the two resonant wavelengths correspond to the same radiation pattern. When the length of the grating is constant, the bandwidth of the long period waveguide grating increases with the increase of the grating constant. When the grating constant is constant, the bandwidth of the long period waveguide grating As the length of grating increases, the depth of filtering decreases with the decrease of grating length.