Vectorial structure of an apertured Gaussian beam in the far field: an accurate method

Based on the angular spectrum representation and the method of stationary phase, an analytical vectorial structure of an apertured Gaussian beam in the far field has been derived without any approximation that is concise and convenient to calculate. The analytical expressions of the energy flux of the transverse electric (TE) term, the transverse magnetic (TM) term, and the apertured Gaussian beam are also presented in the far field. The energy flux distributions of the TE term, the TM term, and the apertured Gaussian beam are numerically demonstrated in the far-field plane. The influences of the linearly polarized angle, the f-parameter, and the truncation parameter on the energy flux distributions in the far field of the TE term, the TM term, and the apertured Gaussian beam are discussed in detail.