实验研究了盐ＬａｎｇｍｕｉｒＢｌｏｄｇｅｔ单分子层膜在不同基频光和倍频光偏振态组合（ｓ→ｐ，ｐ→ｐ和４５°→ｓ）情况下的透射光学二次谐波产生（ＳＨＧ），并利用有关透射方向ＳＨＧ理论公式进行了曲线拟合．结果发现，随着入射角的增大，拟合曲线与实验点存在较大的偏移．这是因为忽略了基频光和倍频光在作为ＬＢ膜衬底的玻璃基板内的多次反射造成的．研究了理论拟合曲线和实验结果偏移的主要原因．并给出了考虑多次反射最低阶修正后的理论公式和拟合曲线．研究结果表明：进行变入射角情况下的透射ＳＨＧ研究时，特别是当测量涉及到ｓ偏振态时，如果要固定探测装置的位置不变，那么玻璃内的多次反射必须加以考虑 The transmission optical second harmonic generation (SHG) of LangmuirBlodget monolayer films with different combinations of fundamental frequency and frequency polarization states (s → p, p → p and 45 ° → s) ), And using the SHG theoretical formula for the transmission curve fitting. The results show that with the increase of incident angle, there is a big deviation between the fitted curve and experimental point. This is because the fundamental frequency light and frequency doubling light are ignored due to multiple reflections in the glass substrate as an LB film substrate. The main reason for the deviation of theoretical fitting curve and experimental result is studied. The theoretical formula and the fitted curve considering the lowest order of multiple reflections are given. The results show that multiple reflections in the glass must be taken into account when performing the SHG study at varying incidence, especially when the s-polarization state is involved in the measurement, and the position of the stationary sensing device is constant