Theory Of Intracavity Adaptive Optic Mode Control

A theoretical treatment of the influence linear intracavity phase aberrations have upon the transverse mode structure of an unstable cavity and the ideal compensation of such aberrations by an intracavity adaptive optic element is provided. Numerical calculations of the aberration sensitivity and the corrective capabilities afforded by such an ideally configured adaptive optic element demonstrate the accuracy of this analysis. A numerical analysis of the system performance obtained in a recent adaptive laser experiment shows that the multidither approach does not yield the optimum correction. As a consequence, it is suggested that the best approach to applying adaptive optics to intracavity mode control is to calculate the precise mirror surface profile from measurements of the outcoupled phase structure weighted by the appropriate theoretical aberration sensitivity coefficient.