This paper proposes an iteration-free near to far field transformation for estimation of directive radiators' beam-width. Near field amplitudes are scanned on two planes, and they are used to scale the radiation matrix that relates the complex-valued fields on the two planes. It is shown that an eigen-vector of the scaled radiation matrix represents the phase of the field on the first plane. With the scanned amplitude and the retrieved phase, the radiation pattern is calculated based on Huygens' principle. Due to the limited size of the scanning plane, the side-lobe of the radiation pattern is shifted, but the main lobe is accurately reconstructed. Therefore, the proposed method is useful for estimating the beam-width of directive radiators.