The fresnel and franhufer diffraction patterns , of regular shapes screen such as slits , rectangular apertures , circle apertures , discs , triangle apertures , ronchi gratings , and some irregular shapes screen , are observed in the different propagation distance . this clearly gives the relation and difference of the two diffraction patterns 具體分析了規則形狀如單縫、矩孔、圓孔、圓盤、三角孔、黑白光柵及一些不規則形狀等孔徑的菲涅耳衍射和夫瑯禾費衍射圖樣強度分布,為深入理解菲涅耳衍射和夫瑯禾費衍射及其內在聯系與區別提供了理論依據。