Laser heterodyne apparatus for measurements of liquid surface properties—Theory and experiments
Laser heterodyne apparatus for measurements of liquid surface properties—Theory and experiments
复制标题
用于测量液体表面特性的激光外差装置理论与实验
DOI：
10.1063/1.322953
复制
发表时间：
1976
影响因子：
3.2
通讯作者：
O. Nilsson
中科院分区：
文献类型：
--
作者：
S. Hård;Y. Hamnerius;O. Nilsson
研制了一种测量液体热激表面毛细波激光散射的仪器。这样的测量不会对所研究的表面造成任何机械或热干扰（使用低功率连续波He - Ne激光器）。这在研究具有生物学意义的薄膜覆盖表面时尤为重要。我们的外差技术装置使用光栅来产生可控的本振光束。这是我们的仪器与以前工人的仪器的主要区别。与这些仪器相比，测量光谱的灵敏度和分辨率都有了很大的提高，由此可以计算液体的表面张力和粘度等性质。提出了一种定量分析理论，该理论允许对测量装置进行优化，并在实际测量中证明了预测的分辨率和灵敏度。结果表明，该方法比早期的方法具有更高的准确性。
An apparatus has been developed, which measures the laser light scattering from thermally excited surface capillary waves of liquids. Such measurements do not cause any mechanical or thermal disturbances of the surface under study (a low‐power cw He‐Ne laser is used). This is especially important in the study of film‐covered surfaces which are biologically interesting. Our heterodyne technique apparatus uses a grating to create a well‐controlled local oscillator light beam. This is the main difference between our apparatus and those of previous workers. Compared with these apparatuses the sensitivity and resolution are considerably improved in the measured spectra, from which liquid properties such as surface tension and viscosity are calculated. A quantitative analytical theory is developed which permits optimization of the measuring set up and it is demonstrated that the predicted resolution and sensitivity are obtained in the practical measurements. It is demonstrated with higher accuracy than in earli...