When these organic materials meet each other they may form exciplex which introduce new spectral lines and reduce original ones . we compared the spectra of samples ito / tvk : tpb / alg3 / al and ito / pvk : tpb / mgf / alg3 / al . we found that the spectrum from exciplex is much reduced 有机材料的载流子迁移率低,不可能实现碰撞离化,它的发光只能是和阴极射线管中的发光一样,来源于从sioz加速出来的电子对有机材料的直接碰撞。