According to the Fresnel-Kirchhoff diffraction formula this thesis gets the light strength progression solution of the Fraunhofer diffraction field through the integral expression of the Bessel function, and gives further discussion of the basic characters of the Fraunhofer diffraction field. 根据菲涅耳基尔霍夫衍射公式,利用贝塞尔函数的积分表达式得出夫琅禾费衍射场的光强级数解,进而讨论了衍射场的基本特征。