用焦平面成像法测量液相扩散系数的研究进展

Research progress of measuring liquid diffusion coefficients based on focal plane imaging method

系统地介绍了一种能够快速、准确测量液相扩散系数的新方法——液芯柱透镜焦平面成像法.该方法利用柱型液芯透镜特有的折射率空间分辨测量能力,结合Fick第二定律测量液相扩散系数.为提高液相扩散系数的测量精度,液芯柱透镜需要具有较高的折射率灵敏度,较小的焦距测量偏差和较小的最小可分辨折射率改变量;同时需要减小球差以保证扩散图像的成像质量.根据不同需求我们分别设计并制作了玻璃毛细管、对称液芯柱透镜、非对称液芯柱透镜和双液芯柱透镜,用于快速、准确、稳定地测量液相扩散系数.基于液芯柱透镜焦平面成像法的测量仪器,能够发展成为一种具有完全自主知识产权的液相扩散系数测量仪.

In this paper,a new method of the focal plane imaging for measuring liquid diffusion coefficient （D） quickly and accurately is described systematically.With the unique spatially resolving ability of liquid-core cylindrical lenses （LCL）for measuring refractive index （RI）,D is measured by Fick＇ s second law.In order to improve the measurement accuracy of D, the LCL must own high refractive index sensitivity, small measurement error of focal length, and the small measurement accuracy of n value ; at the same time, the spherical aberration （SA） should be reduced to ensure the imaging quality of the diffusion image.According to different needs,we de- signed and fabricated glass capillary, symmetric liquid-core cylindrical lens （SLCL） ,asymmetric liquid-core cy- lindrical lens （ALCL） and double liquid cylindrical lens （DLCL） respectively,for measuring liquid diffusion co- efficient（D） quickly, accurately and stably.The measuring instrument based on the method of focal plane imaging can be developed into a D measuring instrument with complete independent intellectual property rights.