Measurement of surface tension and contact angle using entropic edge detection

This paper presents a new method to measure the surface tension and the contact angle of a liquid. The measurement procedure comprises three steps: acquisition of the liquid drop image, image segmentation to obtain the contour of the drop and surface-tension and contact-angle calculation by the ADSA method. In the second step a new segmentation method is used based on the Jensen-Shannon divergence, an entropic measurement of coherence among distribution probabilities. The advantages of using this entropic edge-detection method are shown; it is especially suitable when the source image of the drop is affected by any kind of noise, blur or low-contrast effect. Results reveal a better performance than other methods used in this field.