Mirzaei M
Department of Engineering, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran.
Micron. 2017 Nov;102:65-72. doi: 10.1016/j.micron.2017.09.001. Epub 2017 Sep 5.
The drop hitting a solid surface may be symmetric or asymmetric, which depends on the surface texture and external force orientations. The accurate measurement of the contact angle is of fundamental importance for the purpose of scientific research, while having a substantial role in a wide range of practical applications. This paper presents a new image processing based method, as a computational scheme to measure the inclination angle of apparent edge curves in digital images. The main concept of the scheme is the emulation of a moving goniometer mask coupled with a Gaussian weighted function, which does not require edge fitting with analytic curves for the angle calculation. The algorithm produces as follow: allocating the exact position of the contact points by Harris corner detector function, selecting a series of points on the drop boundary near the contact points, setting goniometric mask on each given point and calculating the angles, applying the Gaussian weighted average function on the calculated angles and measure the objective contact angle. The scheme is tested on several images from recent studies in the available literature. The comparison between analytical and calculated angles shows less than 1° difference.
液滴撞击固体表面时可能是对称的，也可能是不对称的，这取决于表面纹理和外力方向。准确测量接触角对于科学研究至关重要，同时在广泛的实际应用中也发挥着重要作用。本文提出了一种基于图像处理的新方法，作为一种计算方案来测量数字图像中表观边缘曲线的倾斜角。该方案的主要概念是模拟一个移动的测角仪掩膜并结合高斯加权函数，在计算角度时不需要用解析曲线进行边缘拟合。该算法如下：通过哈里斯角点检测函数确定接触点的精确位置，在接触点附近的液滴边界上选择一系列点，在每个给定的点上设置测角仪掩膜并计算角度，对计算出的角度应用高斯加权平均函数并测量目标接触角。该方案在现有文献中近期研究的几张图像上进行了测试。分析角度和计算角度之间的比较显示差异小于1°。
