Effect of optical aberrations on the output quality of a two-element laser

The effect of slight aberrations of an intracavity lens on the mode structure and the quality of the output from a two-element multimode laser is examined theoretically. The coefficients of the mode distortion due to optical aberrations of the intracavity elements are derived by perturbation theory. A general condition for the dynamic stability of the cavity of a two-element laser with respect to small fluctuations of the lens power of the active-element thermal lens is proposed. Recommendations are offered for optimizing the optical layout of the cavity of a two-element solid state laser. These recommendations are aimed at reducing the effect of aberrations on the quality of the transverse structure of the output. The procedure for designing an effective layout for a cavity of a two-element, solid-state industrial laser is illustrated.