The transfer of TEM00 and TEM01 beams through a hard-aperture

摘要

We determine the far-field divergence angle theta(00) (theta(01)) resulting from the diffraction of a TEM00 (TEM01) beam incident on a circular aperture. It is demonstrated that, with a suitable choice of the aperture radius, the ratio theta(01)/theta(00) is enhanced to about 2, while its value is 1.64 without the aperturing effect. It is shown that this effect allows high discrimination between TEM00 and TEM01 modes either in the case of a spatial filter or in the case of an apertured resonator. [References: 16]