提出一种扩展或收缩气／液界面单分子层的分子密度，用荧光成像技术检测单分子层的扩展或收缩效果的新方法———垂悬液滴分析方法．此方法通过改变液滴体积，对液滴界面上的表面活性剂分子实施扩展和收缩，具有ＬａｎｇｍｕｉｒＢｌｏｄｇｅｔ（ＬＢ槽）的功能．对表面活性剂荧光分子，用液滴的激光感生荧光图像，可以实时测量液滴界面的相对分子密度变化；用偏振荧光分析技术，可获取荧光偶极矩在液滴界面的相对取向．对罗丹明（Ｂ）表面活性剂分子ＯＤＲＢ的实验结果表明：１）表面单分子层分子密度在压缩过程中遵循σ／σ０＝（Ｄ０／Ｄ）２规律；２）ＯＤＲＢ分子是以接近“平躺”的方式吸附在液滴界面 A new method of expanding and contracting the molecular density of monomolecular layer at gas / liquid interface and detecting the effect of expanding or contracting monolayer by fluorescence imaging technique is proposed. By changing the volume of the droplet, the method expands and contracts the surfactant molecules on the droplet interface and has the function of LangmuirBlodget (LB groove). For the fluorescent molecules of surfactant, the laser-induced fluorescence images of droplets can be used to measure the relative molecular density changes at the droplet interface in real time. The relative orientation of the fluorescence dipole moment at the droplet interface can be obtained by polarization fluorescence analysis. The experimental results on the surfactant molecule ODRB of rhodamine (B) show that: 1) the molecular density of the surface monolayer follows the rule of σ / σ0 = (D0 / D) 2 during compression; 2) Lying "approach to the droplet interface