Abstract: The light propagation characteristic in one-dimensional function photonic crystal with defect is studied by transfer matrix,compared with the function photonic crystal without defect layer.There is defect mode in the band gap.The defect mode is greatly related with the position and refractive index of defect layer.With the changing position of the defect layer,the defect mode is weak.The position and refractive index of defect also have the effect on the distribution of election field.

Key words: linear , function photon crystals;transfer matrix;defect mode;transmissivity;electronic field distribution