Phase conjugation method for the compensation of thermal defocusing of the light beams

Nonlinear distortions of light beams traveling under thermal self-interaction conditions can be compensated by an algorithm for the control of the initial beam profile. In the linear case the proposed algorithm for the optimization of the process of focusing of a light beam by the conditional gradient method is identical with the familiar phase conjugation algorithm. This analogy is used to investigate a number of problems relating to the efficiency of phase-conjugate adaptive optical systems.