Abstract

Many diffraction calculations have been carried out up to now, both numerical and analytical, to determine the transversemode properties of laser resonators. Generally these calculations have been based on simplifying assumptions to reduce the problem complexity and, consequently, have been limited to only a few configurations, while more extensive analyses have considered only the eigenmodes of conventional, empty resonators. In particular, little attention has been paid to investigate the transverse-mode properties of optical cavities equipped with interferometric frequency filtering elements (IFFEs), such as etalons, or multipass interferometric reflectors, which are utilized for achieving single-longitudinalmode operation, narrow-band frequency tuning, and shot-to-shot output frequency stabilization. One can expect that the presence of these optical elements modifies both the spatial and spectral features of the oscillating modes, since it has been demonstrated that their insertion in an optical cavity induces nonlinear variations of the phase of the cavity's electric field that is equivalent to an actual change of the cavity length.¹

© 1994 IEEE