Photorefractive two-wave mixing in the presence of an incoherent beam

We present the numerical results of the photorefractive two-wave mixing in the presence of an incoherent beam by considering the influence of the rati os of the intensities and the light-excitation cross sections of the incohe rent beam to the coherent beams on the space-charge field and the effective coupling coefficient. The results show that the incoherent beam can contro l the intensity of the coherent beams effectively. The experimental results agree with the theory well. One application is demonstrated to obtain the positive and negative coherent replicas of an incoherent image. The coheren t images have a resolution of 80.6 line pairs/mm.