The discovery of phase compensation instabilities has made conjugate field compensation an important research topic of high energy laser atmospheric propagation. Mr. Karr presented a scheme to produce conjugate field using two deformable mirrors, and gave an algorithm for uniform intensity source. In this paper, for nonuniform intensity source we present an algorithm composed of a linearized algorithm and a perturbation approximation algorithm. The algorithm is demonstrated effective by simulations using a Gaussian beam source. The simulations show that the smooth surface of deformable mirror eliminates the local phase fluctuations on the first mirror, evidently improving the intensity pattern on the second mirror, and that for the Gaussian beam, the needed phase is easily constructed by deformable mirrors. The effect of the distance between the mirrors on the requirement for phase performance range is also discussed, with some suggestions to reduce the performance range requirement.