两种光子晶体滤波器性能的比较

Filtering performance comparision of two types of photonic crystal filter

利用传输矩阵法,通过分别计算由高折射率介质与金属叠加而成的多层膜和由高、低折射率介质交替排列、中间含有间隔的复式膜的透射率,比较了与这两种膜对应的多层膜滤波器和复式膜滤波器的滤波特性。结果表明:多层膜滤波器的角度宽容性较好,但单色性和透射性较差,此类滤波器适合于入射角变化大,但对单色性和透射性要求不高的情况。而复式膜滤波器的性能恰好和多层膜滤波器的相反,特别适合小角度入射的情况。

With the method of transfer matrix,the performances of two types of photonic crystal film filters are compared.The filters are the multilayer film filter composed by the stackings of high refractive index medium and metal material and the composite film filter with an alternate alignment of high and low refractive index mediums and gaps.The results indicate that multilayer film filters have larger angle tolerance,but poor monochromaticity and transmittance,thus they are suitable to be used when there is a large change of incidence angle but no high requirement of monochromaticity and transmittance.On the other hand,composite film filters′ performances have contrary characteristics,so they are suitable in small incidence case.