CRITERIA FOR EVALUATING THE ACCURACY OF SURFACE TENSION VALUES FROM DIGITAL VISION SYSTEMS

Publisher Website
Google Scholar
Abstract
Experimental techniques for measuring surface tension using the shape of either axisymmetric sessile or pendant drops have existed for many years. Recent developments in digital image acquisition and processing have permitted the computerization of the process, by which the coordinates of the drop’s edge profile are obtained. Algorithms like the axisymmetric drop shape analysis–profile (ADSA–P) program use the edge profile coordinates to estimate quantities such as the surface tension, drop volume, and contact angle. The precision of these estimated quantities depends on various effects that influence the accuracy by which the edge profile coordinates are acquired. We have modeled this uncertainty in coordinate information as a perturbation effect and related the size of the perturbation to the surface tension accuracy. Two analogous relations were used to set regions of surface tension accuracy, e.g., or as functions of the magnification of the drop, CCD camera array size, pixel size, drop shape, and drop edge precision. An algorithm for the design of various vision systems based on these criteria will be discussed and illustrated.

This publication has 19 references indexed in Scilit: