Normal oscillation modes of a conjugate resonator with an array-type controlled transparency

An analysis is made of the configuration of the field and losses experienced by normal oscillation modes of a conjugate resonator with an array-type controlled transparency. It is shown that the presence of gaps between the active areas of a transparency results in deformation of the normal modes in such a resonator, compared with a resonator which has a continuous aperture. Computer calculations are reported of the distribution of the field of normal modes on a resonator mirror and of the dependence of the losses experienced by the modes on the Fresnel number of the resonator. It is shown that the dependence has certain singularities corresponding to qualitative changes in the structure of normal modes, resulting in a considerable increase of the angular divergence. These features of the behavior of normal oscillation modes are supported by experiments carried out as part of the present study.