© 2019 IEEE.In the computation of the electromagnetic wave scattering, the different techniques can be combined together as hybrid methods. The Complex Source Point (CSP) techniques can also be used for this purpose and combined with the Method of Moments (MoM) easily. In 2D scattering problems, the CSP method can be used to convert an isotropic line source radiation to a directive beam with a similar type Green's function expression. By using this CSP type Green's function, the surface current radiates as a beam nature and the interaction between the far elements can be approximated as zero. Hence, the main matrix was strongly localized. But in this study, a surface field distribution in finite width is introduced to the formulation and it is used in the definition of a new Green's function. This new Green's function has a beam aperture localized on the surface and its beam width can be reduced to a few basis function levels by using a generalized pencil of beam function (GPOF) method. This localization of Green's function gives rise to the sparsity in the main matrix. Then the memory storage and the overall running times become smaller so that the larger sizes can be modeled with the smaller computational times.