实验上实现了低频液体表面波的激光衍射,提出了激光衍射法测量液体表面张力和表面压。当激光斜入射到几百赫兹液体表面波上,观察到反射光形成稳定的、清晰的衍射光斑。理论上导出了衍射光斑的角宽度和表面波波长的解析关系,实验上验证了液体表面波的色散关系,计算了蒸馏水的表面张力和蒸馏水中加入不溶性表面活性剂———“苯”单分子膜的表面压。根据其机理,建立起一种实时、非接触测量液体表面张力和表面压的实用方法。 The laser diffraction of low frequency liquid surface wave was experimentally achieved, and the laser diffraction method was proposed to measure the liquid surface tension and surface pressure. When the laser is obliquely incident on liquid surface waves of hundreds of Hertz, the reflected light is observed to form a stable, sharp diffraction spot. The analytical relationship between the angular width of the diffracted light spot and the wavelength of the surface wave is theoretically derived. The dispersion relation of the liquid surface wave is experimentally verified. The surface tension of the distilled water and the insoluble surfactant - “benzene” Surface pressure of the membrane. According to its mechanism, a real-time, non-contact measurement of liquid surface tension and surface pressure of practical methods.