Abstract:Using disperse orange 25 as guest dye , the doped film sample of organic polymer PMMA was fabricated and all optical poled. The stronger the intensity of the two writing light beams are , the faster the second order susceptibility for the second nonlinear optical effect by the all optical poling achieves the saturation. The quality of the second nonlinear optical effect in the film was affected by several factors such as the difference of phase , the ratio of intensities of light beams ,and the ratio of intensity of optical fields of the two writing beams.