The nonlinear optical (Nonlinear Optics, NL0) is a new field of modern optics is the study of science and the field in response to material presented in the light of the role of strong nonlinear relationships. Among the non-linear optical effect, the SHG (SHG) is the most striking is the most studied nonlinear effects. Nonlinear optical material effect on modern science and technology, especially in a number of civilian and military high-tech areas, such as optoelectronic communications, optical information storage, integrated circuits, optical switching, optical limiters, color laser printing, laser blinding weapons marine fish finding, which have a series of important applications.