画像処理を用いた微小液体流量計測法の開発

抄録

To develop a system that measures the flow rate of several nl/min with 1% uncertainty by acquiring the moving speed of the liquid meniscus in the capillary using image processing, we performed a fundamental verification of the measurement method by creating an image processing program that determines the position of the liquid meniscus in the capillary and calculates the flow rate. We recorded the meniscus moving inside a glass capillary (inner diameter is 2 mm) using a high speed camera and tracked the meniscus by the image processing program we created. Although the meniscus can be tracked, the accuracy of themeniscus position obtained is unclear because the shape of the meniscus is yet to be considered. The major factors of flow rate uncertainty are the time and spatial resolutions of the camera, as well as the uncertainty of the inner diameter of the capillary. When the time resolution is 0.02 second, the spatial resolution is 0.1328 mm, and measurement time is less than 500 seconds, with a capillary of inner diameters of 0.1 to 2 mm, it is impossible to achieve a 10 nl/min flowrate measurement uncertainty of 1% or less. In order to achieve that, it is necessary to improve the spatial resolution of the camera by narrowing the capturing range.